Bought it 6 months ago, and still haven't finished a single game. The crashes become more and more frequent as the game progresses. I set it to autosave EVERY turn to try to play through a game, but in the end I gave up. Restarting takes quite a long time, and it's just not enjoyable anymore.
Add to that the hopeless difference between the PC and mac versions (because the mac version just never gets updated) and the use of Steam (to be nice I'll call it "not quite user friendly", or maybe "a somewhat confused implementation of drm"), and the choice is simple. Don't bother.
The 75% off deal suggests that they've given up on making the game work, and are now milking the last few suckers.
Btw, I'm running it on a 2010 8-core mac pro with 24 Gigs. You could say that I am not resource limited.
strange that one person crashes constantly while others have no issue at all. maybe its the system itself? I would blame opengl driver to be truthful. maybe the driver doesnt agree with the system.