Here's the next test version:
Class System v5 beta
I've fixed the WEAPONINFO_ALT and it was as I suspected, I'd forgotten to add the XM-18 grenade launcher and that caused the CTD.
I've also divided the parameter selection page into 2 pages, since you reported a CTD I checked the log myself, and iven if I dint get a CTD there was a warning about scrolling. Once I divided those screens the warning disappeared and I hope your CTD's will as well.