diff --git a/build.cake b/build.cake
index 81352cb..5127451 100644
--- a/build.cake
+++ b/build.cake
@@ -1,6 +1,5 @@
-#tool nuget:?package=NUnit.ConsoleRunner&version=3.6.1
+#tool nuget:?package=NUnit.ConsoleRunner&version=3.7.0
 #tool nuget:?package=GitVersion.CommandLine
-#addin "Cake.Incubator"
 
 using System.Text.RegularExpressions;
 
diff --git a/build.ps1 b/build.ps1
index 519ad09..d24357a 100644
--- a/build.ps1
+++ b/build.ps1
@@ -1,55 +1,222 @@
+##########################################################################
+# This is the Cake bootstrapper script for PowerShell.
+# This file was downloaded from https://github.com/cake-build/resources
+# Feel free to change this file to fit your needs.
+##########################################################################
+
+<#
+
+.SYNOPSIS
+This is a Powershell script to bootstrap a Cake build.
+
+.DESCRIPTION
+This Powershell script will download NuGet if missing, restore NuGet tools (including Cake)
+and execute your Cake build script with the parameters you provide.
+
+.PARAMETER Script
+The build script to execute.
+.PARAMETER Target
+The build script target to run.
+.PARAMETER Configuration
+The build configuration to use.
+.PARAMETER Verbosity
+Specifies the amount of information to be displayed.
+.PARAMETER ShowDescription
+Shows description about tasks.
+.PARAMETER DryRun
+Performs a dry run.
+.PARAMETER Experimental
+Uses the nightly builds of the Roslyn script engine.
+.PARAMETER Mono
+Uses the Mono Compiler rather than the Roslyn script engine.
+.PARAMETER SkipToolPackageRestore
+Skips restoring of packages.
+.PARAMETER ScriptArgs
+Remaining arguments are added here.
+
+.LINK
+https://cakebuild.net
+
+#>
+
+[CmdletBinding()]
 Param(
     [string]$Script = "build.cake",
-    [string]$Target = "Default",
-    [ValidateSet("Release", "Debug")]
-    [string]$Configuration = "Release",
+    [string]$Target,
+    [string]$Configuration,
     [ValidateSet("Quiet", "Minimal", "Normal", "Verbose", "Diagnostic")]
-    [string]$Verbosity = "Verbose",
+    [string]$Verbosity,
+    [switch]$ShowDescription,
+    [Alias("WhatIf", "Noop")]
+    [switch]$DryRun,
     [switch]$Experimental,
-    [switch]$WhatIf
+    [switch]$Mono,
+    [switch]$SkipToolPackageRestore,
+    [Parameter(Position=0,Mandatory=$false,ValueFromRemainingArguments=$true)]
+    [string[]]$ScriptArgs
 )
 
+[Reflection.Assembly]::LoadWithPartialName("System.Security") | Out-Null
+function MD5HashFile([string] $filePath)
+{
+    if ([string]::IsNullOrEmpty($filePath) -or !(Test-Path $filePath -PathType Leaf))
+    {
+        return $null
+    }
+
+    [System.IO.Stream] $file = $null;
+    [System.Security.Cryptography.MD5] $md5 = $null;
+    try
+    {
+        $md5 = [System.Security.Cryptography.MD5]::Create()
+        $file = [System.IO.File]::OpenRead($filePath)
+        return [System.BitConverter]::ToString($md5.ComputeHash($file))
+    }
+    finally
+    {
+        if ($file -ne $null)
+        {
+            $file.Dispose()
+        }
+    }
+}
+
+Write-Host "Preparing to run build script..."
+
+if(!$PSScriptRoot){
+    $PSScriptRoot = Split-Path $MyInvocation.MyCommand.Path -Parent
+}
+
 $TOOLS_DIR = Join-Path $PSScriptRoot "tools"
+$ADDINS_DIR = Join-Path $TOOLS_DIR "Addins"
+$MODULES_DIR = Join-Path $TOOLS_DIR "Modules"
 $NUGET_EXE = Join-Path $TOOLS_DIR "nuget.exe"
 $CAKE_EXE = Join-Path $TOOLS_DIR "Cake/Cake.exe"
+$NUGET_URL = "https://dist.nuget.org/win-x86-commandline/latest/nuget.exe"
+$PACKAGES_CONFIG = Join-Path $TOOLS_DIR "packages.config"
+$PACKAGES_CONFIG_MD5 = Join-Path $TOOLS_DIR "packages.config.md5sum"
+$ADDINS_PACKAGES_CONFIG = Join-Path $ADDINS_DIR "packages.config"
+$MODULES_PACKAGES_CONFIG = Join-Path $MODULES_DIR "packages.config"
 
-# Should we use experimental build of Roslyn?
-$UseExperimental = "";
-if($Experimental.IsPresent) {
-    $UseExperimental = "-experimental"
+# Make sure tools folder exists
+if ((Test-Path $PSScriptRoot) -and !(Test-Path $TOOLS_DIR)) {
+    Write-Verbose -Message "Creating tools directory..."
+    New-Item -Path $TOOLS_DIR -Type directory | out-null
 }
 
-# Is this a dry run?
-$UseDryRun = "";
-if($WhatIf.IsPresent) {
-    $UseDryRun = "-dryrun"
+# Make sure that packages.config exist.
+if (!(Test-Path $PACKAGES_CONFIG)) {
+    Write-Verbose -Message "Downloading packages.config..."
+    try { (New-Object System.Net.WebClient).DownloadFile("https://cakebuild.net/download/bootstrapper/packages", $PACKAGES_CONFIG) } catch {
+        Throw "Could not download packages.config."
+    }
 }
 
-# Try download NuGet.exe if do not exist.
+# Try find NuGet.exe in path if not exists
 if (!(Test-Path $NUGET_EXE)) {
-    Invoke-WebRequest -Uri http://nuget.org/nuget.exe -OutFile $NUGET_EXE
+    Write-Verbose -Message "Trying to find nuget.exe in PATH..."
+    $existingPaths = $Env:Path -Split ';' | Where-Object { (![string]::IsNullOrEmpty($_)) -and (Test-Path $_ -PathType Container) }
+    $NUGET_EXE_IN_PATH = Get-ChildItem -Path $existingPaths -Filter "nuget.exe" | Select -First 1
+    if ($NUGET_EXE_IN_PATH -ne $null -and (Test-Path $NUGET_EXE_IN_PATH.FullName)) {
+        Write-Verbose -Message "Found in PATH at $($NUGET_EXE_IN_PATH.FullName)."
+        $NUGET_EXE = $NUGET_EXE_IN_PATH.FullName
+    }
 }
 
-# Make sure NuGet exists where we expect it.
+# Try download NuGet.exe if not exists
 if (!(Test-Path $NUGET_EXE)) {
-    Throw "Could not find NuGet.exe"
+    Write-Verbose -Message "Downloading NuGet.exe..."
+    try {
+        (New-Object System.Net.WebClient).DownloadFile($NUGET_URL, $NUGET_EXE)
+    } catch {
+        Throw "Could not download NuGet.exe."
+    }
 }
 
-# Restore tools from NuGet.
-Push-Location
-Set-Location $TOOLS_DIR
-Invoke-Expression "$NUGET_EXE install -ExcludeVersion"
-Pop-Location
-if ($LASTEXITCODE -ne 0) {
-    exit $LASTEXITCODE
+# Save nuget.exe path to environment to be available to child processed
+$ENV:NUGET_EXE = $NUGET_EXE
+
+# Restore tools from NuGet?
+if(-Not $SkipToolPackageRestore.IsPresent) {
+    Push-Location
+    Set-Location $TOOLS_DIR
+
+    # Check for changes in packages.config and remove installed tools if true.
+    [string] $md5Hash = MD5HashFile($PACKAGES_CONFIG)
+    if((!(Test-Path $PACKAGES_CONFIG_MD5)) -Or
+      ($md5Hash -ne (Get-Content $PACKAGES_CONFIG_MD5 ))) {
+        Write-Verbose -Message "Missing or changed package.config hash..."
+        Remove-Item * -Recurse -Exclude packages.config,nuget.exe
+    }
+
+    Write-Verbose -Message "Restoring tools from NuGet..."
+    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$TOOLS_DIR`""
+
+    if ($LASTEXITCODE -ne 0) {
+        Throw "An error occured while restoring NuGet tools."
+    }
+    else
+    {
+        $md5Hash | Out-File $PACKAGES_CONFIG_MD5 -Encoding "ASCII"
+    }
+    Write-Verbose -Message ($NuGetOutput | out-string)
+
+    Pop-Location
+}
+
+# Restore addins from NuGet
+if (Test-Path $ADDINS_PACKAGES_CONFIG) {
+    Push-Location
+    Set-Location $ADDINS_DIR
+
+    Write-Verbose -Message "Restoring addins from NuGet..."
+    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$ADDINS_DIR`""
+
+    if ($LASTEXITCODE -ne 0) {
+        Throw "An error occured while restoring NuGet addins."
+    }
+
+    Write-Verbose -Message ($NuGetOutput | out-string)
+
+    Pop-Location
+}
+
+# Restore modules from NuGet
+if (Test-Path $MODULES_PACKAGES_CONFIG) {
+    Push-Location
+    Set-Location $MODULES_DIR
+
+    Write-Verbose -Message "Restoring modules from NuGet..."
+    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$MODULES_DIR`""
+
+    if ($LASTEXITCODE -ne 0) {
+        Throw "An error occured while restoring NuGet modules."
+    }
+
+    Write-Verbose -Message ($NuGetOutput | out-string)
+
+    Pop-Location
 }
 
 # Make sure that Cake has been installed.
 if (!(Test-Path $CAKE_EXE)) {
-    Throw "Could not find Cake.exe"
+    Throw "Could not find Cake.exe at $CAKE_EXE"
 }
 
+
+
+# Build Cake arguments
+$cakeArguments = @("$Script");
+if ($Target) { $cakeArguments += "-target=$Target" }
+if ($Configuration) { $cakeArguments += "-configuration=$Configuration" }
+if ($Verbosity) { $cakeArguments += "-verbosity=$Verbosity" }
+if ($ShowDescription) { $cakeArguments += "-showdescription" }
+if ($DryRun) { $cakeArguments += "-dryrun" }
+if ($Experimental) { $cakeArguments += "-experimental" }
+if ($Mono) { $cakeArguments += "-mono" }
+$cakeArguments += $ScriptArgs
+
 # Start Cake
-Invoke-Expression "$CAKE_EXE `"$Script`" -target=`"$Target`" -configuration=`"$Configuration`" -verbosity=`"$Verbosity`" $UseDryRun $UseExperimental"
-Write-Host
-exit $LASTEXITCODE
\ No newline at end of file
+Write-Host "Running build script..."
+&$CAKE_EXE $cakeArguments
+exit $LASTEXITCODE
diff --git a/build.sh b/build.sh
index b9f997f..e5a95bc 100755
--- a/build.sh
+++ b/build.sh
@@ -1,40 +1,64 @@
-#!/bin/bash
-###############################################################
-# This is the Cake bootstrapper script that is responsible for
-# downloading Cake and all specified tools from NuGet.
-###############################################################
+#!/usr/bin/env bash
+
+##########################################################################
+# This is the Cake bootstrapper script for Linux and OS X.
+# This file was downloaded from https://github.com/cake-build/resources
+# Feel free to change this file to fit your needs.
+##########################################################################
 
 # Define directories.
 SCRIPT_DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
 TOOLS_DIR=$SCRIPT_DIR/tools
+ADDINS_DIR=$TOOLS_DIR/Addins
+MODULES_DIR=$TOOLS_DIR/Modules
 NUGET_EXE=$TOOLS_DIR/nuget.exe
 CAKE_EXE=$TOOLS_DIR/Cake/Cake.exe
+PACKAGES_CONFIG=$TOOLS_DIR/packages.config
+PACKAGES_CONFIG_MD5=$TOOLS_DIR/packages.config.md5sum
+ADDINS_PACKAGES_CONFIG=$ADDINS_DIR/packages.config
+MODULES_PACKAGES_CONFIG=$MODULES_DIR/packages.config
+
+# Define md5sum or md5 depending on Linux/OSX
+MD5_EXE=
+if [[ "$(uname -s)" == "Darwin" ]]; then
+    MD5_EXE="md5 -r"
+else
+    MD5_EXE="md5sum"
+fi
 
 # Define default arguments.
 SCRIPT="build.cake"
-TARGET="Default"
-CONFIGURATION="Release"
-VERBOSITY="verbose"
-DRYRUN=false
-SHOW_VERSION=false
+CAKE_ARGUMENTS=()
 
 # Parse arguments.
 for i in "$@"; do
     case $1 in
         -s|--script) SCRIPT="$2"; shift ;;
-        -t|--target) TARGET="$2"; shift ;;
-        -c|--configuration) CONFIGURATION="$2"; shift ;;
-        -v|--verbosity) VERBOSITY="$2"; shift ;;
-        -d|--dryrun) DRYRUN=true ;;
-        --version) SHOW_VERSION=true ;;
+        --) shift; CAKE_ARGUMENTS+=("$@"); break ;;
+        *) CAKE_ARGUMENTS+=("$1") ;;
     esac
     shift
 done
 
+# Make sure the tools folder exist.
+if [ ! -d "$TOOLS_DIR" ]; then
+  mkdir "$TOOLS_DIR"
+fi
+
+# Make sure that packages.config exist.
+if [ ! -f "$TOOLS_DIR/packages.config" ]; then
+    echo "Downloading packages.config..."
+    curl -Lsfo "$TOOLS_DIR/packages.config" https://cakebuild.net/download/bootstrapper/packages
+    if [ $? -ne 0 ]; then
+        echo "An error occured while downloading packages.config."
+        exit 1
+    fi
+fi
+
 # Download NuGet if it does not exist.
-if [ ! -f $NUGET_EXE ]; then
+if [ ! -f "$NUGET_EXE" ]; then
     echo "Downloading NuGet..."
-    curl -Lsfo $NUGET_EXE https://www.nuget.org/nuget.exe
+    curl -Lsfo "$NUGET_EXE" https://dist.nuget.org/win-x86-commandline/latest/nuget.exe
     if [ $? -ne 0 ]; then
         echo "An error occured while downloading nuget.exe."
         exit 1
@@ -42,24 +66,52 @@ if [ ! -f $NUGET_EXE ]; then
 fi
 
 # Restore tools from NuGet.
-pushd $TOOLS_DIR >/dev/null
-mono $NUGET_EXE install -ExcludeVersion
-popd >/dev/null
+pushd "$TOOLS_DIR" >/dev/null
+if [ ! -f "$PACKAGES_CONFIG_MD5" ] || [ "$( cat "$PACKAGES_CONFIG_MD5" | sed 's/\r$//' )" != "$( $MD5_EXE "$PACKAGES_CONFIG" | awk '{ print $1 }' )" ]; then
+    find . -type d ! -name . | xargs rm -rf
+fi
 
-# Make sure that Cake has been installed.
-if [ ! -f $CAKE_EXE ]; then
-    echo "Could not find Cake.exe."
+mono "$NUGET_EXE" install -ExcludeVersion
+if [ $? -ne 0 ]; then
+    echo "Could not restore NuGet tools."
     exit 1
 fi
 
-# Start Cake
-if $SHOW_VERSION; then
-    mono $CAKE_EXE -version
-elif $DRYRUN; then
-    mono $CAKE_EXE $SCRIPT -verbosity=$VERBOSITY -configuration=$CONFIGURATION -target=$TARGET -dryrun
-else
-    mono $CAKE_EXE $SCRIPT -verbosity=$VERBOSITY -configuration=$CONFIGURATION -target=$TARGET
+$MD5_EXE "$PACKAGES_CONFIG" | awk '{ print $1 }' >| "$PACKAGES_CONFIG_MD5"
+
+popd >/dev/null
+
+# Restore addins from NuGet.
+if [ -f "$ADDINS_PACKAGES_CONFIG" ]; then
+    pushd "$ADDINS_DIR" >/dev/null
+
+    mono "$NUGET_EXE" install -ExcludeVersion
+    if [ $? -ne 0 ]; then
+        echo "Could not restore NuGet addins."
+        exit 1
+    fi
+
+    popd >/dev/null
 fi
 
-exit $?
+# Restore modules from NuGet.
+if [ -f "$MODULES_PACKAGES_CONFIG" ]; then
+    pushd "$MODULES_DIR" >/dev/null
 
+    mono "$NUGET_EXE" install -ExcludeVersion
+    if [ $? -ne 0 ]; then
+        echo "Could not restore NuGet modules."
+        exit 1
+    fi
+
+    popd >/dev/null
+fi
+
+# Make sure that Cake has been installed.
+if [ ! -f "$CAKE_EXE" ]; then
+    echo "Could not find Cake.exe at '$CAKE_EXE'."
+    exit 1
+fi
+
+# Start Cake
+exec mono "$CAKE_EXE" $SCRIPT "${CAKE_ARGUMENTS[@]}"
diff --git a/src/demo-assembly/demo-assembly.csproj b/src/demo-assembly/demo-assembly.csproj
index c68f750..1c88716 100644
--- a/src/demo-assembly/demo-assembly.csproj
+++ b/src/demo-assembly/demo-assembly.csproj
@@ -38,9 +38,8 @@
     <Prefer32Bit>false</Prefer32Bit>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="nunit.framework, Version=3.6.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.3.6.1\lib\net45\nunit.framework.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="nunit.framework, Version=3.7.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NUnit.3.7.1\lib\net45\nunit.framework.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.Configuration" />
diff --git a/src/demo-assembly/packages.config b/src/demo-assembly/packages.config
index 8e3be78..48fcf5d 100644
--- a/src/demo-assembly/packages.config
+++ b/src/demo-assembly/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="NUnit" version="3.6.1" targetFramework="net45" />
+  <package id="NUnit" version="3.7.1" targetFramework="net45" />
 </packages>
\ No newline at end of file
diff --git a/src/mock-assembly/mock-assembly.csproj b/src/mock-assembly/mock-assembly.csproj
index a651019..31d8aff 100644
--- a/src/mock-assembly/mock-assembly.csproj
+++ b/src/mock-assembly/mock-assembly.csproj
@@ -63,13 +63,11 @@
     <StartupObject />
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="nunit.framework, Version=3.6.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.3.6.1\lib\net20\nunit.framework.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="nunit.framework, Version=3.7.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NUnit.3.7.1\lib\net20\nunit.framework.dll</HintPath>
     </Reference>
     <Reference Include="NUnit.System.Linq, Version=0.6.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.3.6.1\lib\net20\NUnit.System.Linq.dll</HintPath>
-      <Private>True</Private>
+      <HintPath>..\..\packages\NUnit.3.7.1\lib\net20\NUnit.System.Linq.dll</HintPath>
     </Reference>
     <Reference Include="System">
       <Name>System</Name>
diff --git a/src/mock-assembly/packages.config b/src/mock-assembly/packages.config
index 44dfe16..27e4160 100644
--- a/src/mock-assembly/packages.config
+++ b/src/mock-assembly/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="NUnit" version="3.6.1" targetFramework="net20" />
+  <package id="NUnit" version="3.7.1" targetFramework="net20" />
 </packages>
\ No newline at end of file
diff --git a/src/nunit-gui/nunit-gui.csproj b/src/nunit-gui/nunit-gui.csproj
index 87bef2f..2ed9088 100644
--- a/src/nunit-gui/nunit-gui.csproj
+++ b/src/nunit-gui/nunit-gui.csproj
@@ -37,7 +37,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="nunit.engine.api, Version=3.0.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.Engine.Api.3.6.1\lib\nunit.engine.api.dll</HintPath>
+      <HintPath>..\..\packages\NUnit.Engine.Api.3.7.0\lib\nunit.engine.api.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="System" />
@@ -226,19 +226,19 @@
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
     <Content Include="nunit.ico" />
-    <None Include="..\..\packages\NUnit.Engine.3.6.1\lib\nunit-agent-x86.exe">
+    <None Include="..\..\packages\NUnit.Engine.3.7.0\lib\nunit-agent-x86.exe">
       <Link>nunit-agent-x86.exe</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
-    <None Include="..\..\packages\NUnit.Engine.3.6.1\lib\nunit-agent-x86.exe.config">
+    <None Include="..\..\packages\NUnit.Engine.3.7.0\lib\nunit-agent-x86.exe.config">
       <Link>nunit-agent-x86.exe.config</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
-    <None Include="..\..\packages\NUnit.Engine.3.6.1\lib\nunit-agent.exe">
+    <None Include="..\..\packages\NUnit.Engine.3.7.0\lib\nunit-agent.exe">
       <Link>nunit-agent.exe</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
-    <None Include="..\..\packages\NUnit.Engine.3.6.1\lib\nunit-agent.exe.config">
+    <None Include="..\..\packages\NUnit.Engine.3.7.0\lib\nunit-agent.exe.config">
       <Link>nunit-agent.exe.config</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
diff --git a/src/nunit-gui/packages.config b/src/nunit-gui/packages.config
index b4636e0..2db5070 100644
--- a/src/nunit-gui/packages.config
+++ b/src/nunit-gui/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="NUnit.Engine.Api" version="3.6.1" targetFramework="net20" />
+  <package id="NUnit.Engine.Api" version="3.7.0" targetFramework="net20" />
 </packages>
\ No newline at end of file
diff --git a/src/nunit.gui.core/Model/ResultSummaryReporter.cs b/src/nunit.gui.core/Model/ResultSummaryReporter.cs
index 484b410..dbbbc66 100644
--- a/src/nunit.gui.core/Model/ResultSummaryReporter.cs
+++ b/src/nunit.gui.core/Model/ResultSummaryReporter.cs
@@ -58,7 +58,7 @@ public static string WriteSummaryReport(ResultSummary summary)
 
             writer.AppendLine($"  Start time: {summary.StartTime:u}");
             writer.AppendLine($"    End time: {summary.EndTime:u}");
-            writer.AppendLine($"    Duration: {summary.Duration:0.000}");
+            writer.AppendUICultureFormattedNumber("    Duration: ", summary.Duration);
 
             return writer.ToString();
         }
@@ -68,5 +68,11 @@ private static void AppendUICultureFormattedNumber(this StringBuilder sb, string
             sb.Append(label);
             sb.Append(number.ToString("n0", CultureInfo.CurrentUICulture));
         }
+
+        private static void AppendUICultureFormattedNumber(this StringBuilder sb, string label, double number)
+        {
+            sb.Append(label);
+            sb.Append(number.ToString("n3", CultureInfo.CurrentUICulture));
+        }
     }
 }
\ No newline at end of file
diff --git a/src/nunit.gui.core/nunit.gui.core.csproj b/src/nunit.gui.core/nunit.gui.core.csproj
index 63f8317..97d0561 100644
--- a/src/nunit.gui.core/nunit.gui.core.csproj
+++ b/src/nunit.gui.core/nunit.gui.core.csproj
@@ -32,7 +32,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="nunit.engine.api, Version=3.0.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.Engine.Api.3.6.1\lib\nunit.engine.api.dll</HintPath>
+      <HintPath>..\..\packages\NUnit.Engine.Api.3.7.0\lib\nunit.engine.api.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="System" />
diff --git a/src/nunit.gui.core/packages.config b/src/nunit.gui.core/packages.config
index b4636e0..2db5070 100644
--- a/src/nunit.gui.core/packages.config
+++ b/src/nunit.gui.core/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="NUnit.Engine.Api" version="3.6.1" targetFramework="net20" />
+  <package id="NUnit.Engine.Api" version="3.7.0" targetFramework="net20" />
 </packages>
\ No newline at end of file
diff --git a/src/tests/Model/ResultStateTests.cs b/src/tests/Model/ResultStateTests.cs
index 4ff008f..f83979f 100644
--- a/src/tests/Model/ResultStateTests.cs
+++ b/src/tests/Model/ResultStateTests.cs
@@ -101,7 +101,7 @@ public void Site_ConstructorWithThreeArguments_ReturnsSite(string label, Failure
             Assert.AreEqual(site, resultState.Site);
         }
 
-        [TestCase(TestStatus.Skipped, SpecialValue.Null, "Skipped")]
+        [TestCase(TestStatus.Skipped, null, "Skipped")]
         [TestCase(TestStatus.Passed, "", "Passed")]
         [TestCase(TestStatus.Passed, "testLabel", "Passed:testLabel")]
         public void ToString_Constructor_ReturnsExpectedString(TestStatus status, string label, string expected)
diff --git a/src/tests/Model/ResultSummaryReporterTests.cs b/src/tests/Model/ResultSummaryReporterTests.cs
index 2a58d94..bd8d0a3 100644
--- a/src/tests/Model/ResultSummaryReporterTests.cs
+++ b/src/tests/Model/ResultSummaryReporterTests.cs
@@ -139,13 +139,12 @@ public void ReportContainsExtendedSkipInformationWhenItHasSkips(int ignoreCount,
         }
 
         [Test]
-        public void ReportContainsStartAndEndDateAndDuration()
+        public void ReportContainsStartAndEndDate()
         {
             var summary = new ResultSummary
             {
                 StartTime = new DateTime(2015, 10, 21, 7, 28, 30),
                 EndTime = new DateTime(2015, 10, 21, 16, 20, 45),
-                Duration = 123.456789,
                 OverallResult = String.Empty
             };
 
@@ -153,7 +152,6 @@ public void ReportContainsStartAndEndDateAndDuration()
 
             Assert.That(report, Does.Contain("Start time: 2015-10-21 07:28:30Z"));
             Assert.That(report, Does.Contain("End time: 2015-10-21 16:20:45Z"));
-            Assert.That(report, Does.Contain("Duration: 123.457"));
         }
 
         [Test, SetUICulture("de-DE")]
@@ -171,6 +169,7 @@ public void ReportWithDifferentUICultureFormatsNumbersAccordingToUICulture()
                 InvalidCount = 10000,
                 IgnoreCount = 10000,
                 ExplicitCount = 10000,
+                Duration = 123.456789,
                 OverallResult = String.Empty
             };
 
@@ -188,6 +187,7 @@ public void ReportWithDifferentUICultureFormatsNumbersAccordingToUICulture()
             Assert.That(report, Does.Contain("Skipped Tests - Ignored: 10.000"));
             Assert.That(report, Does.Contain("Explicit: 10.000"));
             Assert.That(report, Does.Contain("Other: 10.000"));
+            Assert.That(report, Does.Contain("Duration: 123,457"));
         }
     }
 }
diff --git a/src/tests/nunit-gui.tests.csproj b/src/tests/nunit-gui.tests.csproj
index 3f42467..0d068fc 100644
--- a/src/tests/nunit-gui.tests.csproj
+++ b/src/tests/nunit-gui.tests.csproj
@@ -32,24 +32,20 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Mono.Cecil, Version=0.9.6.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.Engine.3.6.1\lib\Mono.Cecil.dll</HintPath>
-      <Private>True</Private>
+      <HintPath>..\..\packages\NUnit.Engine.3.7.0\lib\Mono.Cecil.dll</HintPath>
     </Reference>
     <Reference Include="NSubstitute, Version=2.0.3.0, Culture=neutral, PublicKeyToken=92dd2e9066daa5ca, processorArchitecture=MSIL">
       <HintPath>..\..\packages\NSubstitute.2.0.3\lib\net35\NSubstitute.dll</HintPath>
       <Private>True</Private>
     </Reference>
-    <Reference Include="nunit.engine, Version=3.6.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.Engine.3.6.1\lib\nunit.engine.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="nunit.engine, Version=3.7.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NUnit.Engine.3.7.0\lib\nunit.engine.dll</HintPath>
     </Reference>
     <Reference Include="nunit.engine.api, Version=3.0.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.Engine.3.6.1\lib\nunit.engine.api.dll</HintPath>
-      <Private>True</Private>
+      <HintPath>..\..\packages\NUnit.Engine.3.7.0\lib\nunit.engine.api.dll</HintPath>
     </Reference>
-    <Reference Include="nunit.framework, Version=3.6.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\NUnit.3.6.1\lib\net35\nunit.framework.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="nunit.framework, Version=3.7.1.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NUnit.3.7.1\lib\net35\nunit.framework.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.Drawing" />
diff --git a/src/tests/packages.config b/src/tests/packages.config
index a60a598..fed7e59 100644
--- a/src/tests/packages.config
+++ b/src/tests/packages.config
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="NSubstitute" version="2.0.3" targetFramework="net35" />
-  <package id="NUnit" version="3.6.1" targetFramework="net35" />
-  <package id="NUnit.Engine" version="3.6.1" targetFramework="net35" />
+  <package id="NUnit" version="3.7.1" targetFramework="net35" />
+  <package id="NUnit.Engine" version="3.7.0" targetFramework="net35" />
 </packages>
\ No newline at end of file
diff --git a/tools/nuget.exe b/tools/nuget.exe
deleted file mode 100644
index 324daa8..0000000
Binary files a/tools/nuget.exe and /dev/null differ
diff --git a/tools/packages.config b/tools/packages.config
index b9d1383..7ab34be 100644
--- a/tools/packages.config
+++ b/tools/packages.config
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
     <package id="Cake" version="0.19.1" />
-    <package id="NUnit.ConsoleRunner" version="3.6.1" />
+    <package id="NUnit.ConsoleRunner" version="3.7.0" />
 </packages>