On the glitches board at the top there is a Windows 7 thread which says this game is playable on Windows 7. If you tried it and are having a problem you should post on that board.
I think the game requires compatibility mode set to Windows NT in Windows 7. The GOG install will set your compatibility mode for you.
It's also possible that the copy protection the game used has been blocked by a Windows update. According to GCW the English CD version used SafeDisc v2.