imaginaryant

if anyone is still having trouble, I just spent a day chasing it down, first if you use the doom slayer mod, disable that until after you leave vault 111, if you don't use doom slayer then look for anything that adds or completes a quest and make sure its disabled until after you leave vault 111, you will know which one because it will start and/or complete before the bomb falls

check your skse.ini, if the memory patch's DefaultHeapInitialAllocMB setting is set above 768 it will crash at the opening screen if expandsystemmemoryx64 in the enblocal is set to true