Does the crossbow fire before the crash? As in, does the animation sequence begin?
Make sure to check your dump file to see if it is something in your code. Most likely you're doing something the engine isn't liking, so you'll probably get the disassembly screen.
Does it work for that 20 minutes like you intend it to? And as PM said, what part is it crashing in ( from the META_LOG output... )
EDIT:
What are you trying to do here in UpdateCrossbow?
Code:
if( playerinfomanager != NULL )
playerinfomanager->GetGlobalVars()->curtime + ss_crossbow_refire.GetFloat();
I know there's a bug in HL2DM that causes problems with the crossbow not firing when you expect it to. It's related to the animation sequences and the timing. Could it be that you are changing one of the offsets during an animation cycle? i.e. IN_RELOAD_OFFSET ?