I just got the game 2 days ago. I was shooting arrows at that first cave mage and it crashed to the desktop. It happened really quick, no memory dump, nothing. It's only happened once out of 6 hours of play time so it's not that bad.
I'm using Win2k, BTW.
The main forum says a patch is in the works.
A side question... If I install an add-on do I need to restart the game from the ship?