I'm having the same problems too - both permanent screen lockups and random unhandled exceptions resulting in the dreaded blue screen of death - but in Steam.
Running Win7 64bit SP1, with Direct X 11, Core i7-2600 with 16G ram. Also running twin AMD 6900 cards in crossfire with latest drivers. All MS updates applied and Comodo av software in game mode (when playing).
I've uninstalled and reinstalled the game - from Steam - & followed steam instructions on verifying the game cache too....no issues there that I can see.
Issues in play;
1. When starting the game, if initiating the game from the desktop link and waiting too long before giving the game permission to start (e.g leaving the UAC pop up on screen for a while before agreeing to give the program access).....crash.
2. When coming to an island and the circle (saving) image comes up, sometimes it just hangs - permanently, forcing a restart.
3. Just for no good reason, cruising along in standard gameplay....crash (normally this is a blue screen of death error).
Its just really unstable boys.
Further, I've tried downloading the 1.02 patch to update my system, but all steam games need to update 'from Steam'......So perhaps Boh-Int can push across your latest patch to Steam HQ for an update to Steam users?? (If you haven't already)....if you have then you'll need to revisit this patch ASAP as it hasn't resolved all the stability issues.
Cheers