Well, not really yet, but there is still hope. The problem was of course that there was no problem here - no crash on any PC. Well, that's how crashes tend to behave. We plan a more thorough check in a special environment together with some other projects with similar issues. I hope then we'll find out what's happening. But that will take a while.
The latest engine release seems to fix this problem. I cannot reproduce it anymore on my pc.
and... yes... there was a suspicious model with skin/no skin mixture (wichtel_rot.mdl).
