Hey,
Having exactly the same problem.... Whenever trying to initiate combat with a new creature, the screen goes black. On the mini-map you can see the crosses for the chars and the enemies and the battle obviously continues as the chars take damage and eventually the red cross disappears (or the char dies).
Saving and reloading the savegame shows the chars again - until you initiate combat again. It happened once or twice until now in Act III when it is happening whenver I initiate combat and the game is therefore unplayable.
I have tried using an old savegame which is ok for a while, but eventually the same thing starts happening again.
Cannot see any solution here, but I thought I would add my two cents and see if anyone else if having the same problem.
I dont recall this happening when I played the game the first time - i.e. pre 1.45 patch.
Sys info:
BD 1.45 on WinXP SP1
Dell 9100 p4 3ghz, Radeon 9700 128mb , DirectX9b etc...
Cheers
Lance