RegString.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;

namespace CM0102Patcher
{
    public class RegString
    {
        public static string GetRegString()
        {
            // if on Mono - don't try this
            if (Program.RunningInMono())
                return "";

            if (Is64BitOperatingSystem())
                return @"HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Sports Interactive Ltd\Championship Manager 01-02";
            else
                return @"HKEY_LOCAL_MACHINE\SOFTWARE\Sports Interactive Ltd\Championship Manager 01-02";
        }

        static bool Is64BitOperatingSystem()
        {
            if (IntPtr.Size == 8)  // 64-bit programs run only on Win64
            {
                return true;
            }
            else  // 32-bit programs run on both 32-bit and 64-bit Windows
            {
                // Detect whether the current process is a 32-bit process 
                // running on a 64-bit system.
                bool flag;
                return ((DoesWin32MethodExist("kernel32.dll", "IsWow64Process") &&
                    IsWow64Process(GetCurrentProcess(), out flag)) && flag);
            }
        }

        static bool DoesWin32MethodExist(string moduleName, string methodName)
        {
            IntPtr moduleHandle = GetModuleHandle(moduleName);
            if (moduleHandle == IntPtr.Zero)
            {
                return false;
            }
            return (GetProcAddress(moduleHandle, methodName) != IntPtr.Zero);
        }

        [DllImport("kernel32.dll")]
        static extern IntPtr GetCurrentProcess();

        [DllImport("kernel32.dll", CharSet = CharSet.Auto)]
        static extern IntPtr GetModuleHandle(string moduleName);

        [DllImport("kernel32", CharSet = CharSet.Auto, SetLastError = true)]
        static extern IntPtr GetProcAddress(IntPtr hModule,
            [MarshalAs(UnmanagedType.LPStr)]string procName);

        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool IsWow64Process(IntPtr hProcess, out bool wow64Process);
    }
}