I have had this same problem, when going from Act 2 to Act 3, I can talk to the Imp, but there is a monster in the field of view that starts to attack at the same time, and as soon as your done talking to the Imp my characters attack the monster and it crashes to desk top. Now I have been able to get a save game with pausing right after talking to the Imp, but since I got past there with doing it this way the game is crashing after 5-10mins of game play, and there is no set thing that I see thats causing it. The most common seem to be when talking to Merchants and going threw there items, and going in and out of Battles, its kind of hard to say because they do seem random for the most part.
Now most of this started after I installed the 1.45 patch, I had been in Act 2 at the time, and got the patch and finished Act 2 on Saturday and since then I have been plauged by crashes. I had a few crashes with 1.44, but not like they are now, with 1.43 I never had any crashes nor did I with the fresh install.
System Spec.
AMD Barton 2800
ATI 9700 pro Catalyst 4.5 Drivers in now, had Catalyst 4.3 in untill lastnight.
1 gig Corsair PC3200 DDR
A7N8X mobo
XP pro SP1 and all crit updates.
When I am playing BD I never had to worry about any of the background programs I had running, but now I have everything shut down, and I still get crashes. I have run virus scans with both Nortons and Defender Pro, and they have found nothing. As it is I am at a loss as to what might be the problem. I have tried running the game at different screen settings and this dont help either. I have also gone back to some of my past saved games from Act 2 and the same thing happens there to. I know that I had problems something like this on my old PC with DD, but when I had DD on here I never had any major problems and through out the whole game I only hand a handful of crashes, and most of them came if I had left the game paused for a few hours and went back to playing.
Any help would be greatful, because I would like to finish this in the next week or so before summer gets here.
4nE