I was having a similar problem, with a gray screen every time I launched the game, locking up the system. I tried just about everything, compatibility settings and whatnot. My system is fully up to date as well. I loaded the program once more, clicked about randomly all over the gray area, and my antivirus program eventually gave me a message about TIMWIN.exe being a trojan. I can only assume this is due to the way that GOG gets rid of protection in some games. In support, they advise turning off programs like antivirus. It's actually good advice, since there are a good number of GOG games that these programs don't like
I'm not sure if it will help your problem, but it's worth a try. Quit or pause your antivirus program, or better yet, make an exception for the executable. If this doesn't work, I apologize. Other than ensuring you have the latest drivers and perform other maintenance for your computer, I can't help you.
Post edited October 15, 2010 by LordKuruku