RE: need a sim on window 7
Yeah I have windows 7 running on 64bit and installed Realflight g3.5 that I was running on XP. When you install the sim you want install it in the program x86 folder. This should correct any issues you are having with a game. If that does not work you can right click on the icon of the game on the desktop and choose compatibility mode and select xp or vista and run as admin. Hope this work for you.
My Realflight g3.5 runs great without doing anything!!!!!