Program.cs

using System;
using System.Globalization;
using System.Windows.Forms;

namespace fyiReporting.RdlDesign
{
    public class Program
    {

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            string version = typeof(Program).Assembly.GetName().Version.ToString().Replace(".", "");
           
            string ipcChannelPortName = string.Format("RdlProject{0}", version); 
            // Determine if an instance is already running?
            bool firstInstance;
            string mName = string.Format("Local\\RdlDesigner{0}", version);         
            //   can't use Assembly in this context
            System.Threading.Mutex mutex = new System.Threading.Mutex(false, mName, out firstInstance);
         
            if (firstInstance)
            {// just start up the designer when we're first in line
				var thread = System.Threading.Thread.CurrentThread;

				try
	            {
                    if (DialogToolOptions.DesktopConfiguration.Language != null)
                    {
                        thread.CurrentCulture = new CultureInfo(DialogToolOptions.DesktopConfiguration.Language);
                    }
                    else
                    {
                        thread.CurrentCulture = new CultureInfo(thread.CurrentCulture.Name);
                    }
				}
	            catch
	            {
					thread.CurrentCulture = new CultureInfo(thread.CurrentCulture.Name);
	            }

				if (thread.CurrentCulture.Equals(CultureInfo.InvariantCulture))
				{
					thread.CurrentCulture = new CultureInfo("en-US");
				}
				// for working in non-default cultures
				thread.CurrentCulture.NumberFormat.NumberDecimalSeparator = ".";
				thread.CurrentUICulture = thread.CurrentCulture;
				
				Application.EnableVisualStyles();
                Application.DoEvents();
                Application.Run(new RdlDesigner(ipcChannelPortName, true));
                return;
            }

            // Process already running.   Notify other process that is might need to open another file
            string[] args = Environment.GetCommandLineArgs();

        }
    }
}