After 2 weeks of debugging found a fix for crashing to desktop on loading a game for BG3.
For win10 x64, enabling Virtual memory option "Automatically manage paging file size for all drives", then do a full restart, completely fixed all crash to desktop problems I have been having with BG3.
My BG3 install folder is on a different drive than my OS.
I hope this helps anyone that was in a similar situation!
