First of all: Nice work, man!
I just played on zp01-umssakuracrashsite, and I was able to reproduce following problem:
On the way down the first tunnel (see attached screenshot), when I lie down, aim the SCAR and fire a hellhound, my Inf crashed every time the very moment the nade hit the ground...
I'll also attach the error messages provided by Inf...
Do you have any idea what I can do against it?
When Maja does the same, her Inf stops playing for about a second and gets a pink screen afterwards. Or her Inf crashes, too...