This game was recommended to me by Sloth, and was dirt cheap on steam so I bought it.
I'll update with a review here, but if anyone else is having a start-up error with the game, I have a solution here:
http://www.gog.com/en/forum/ghost_master/all_ghosts_patchThe steam version of the game has a problem with some older ATI cards and Windows 7 64 bit. The patch works for me!
Will report back when I've played the game some more.