Well, first off you posted a lot more stuff than people would be interested in. Keep it simple. You didn't mention if you are using the steam version. If so, go to your games on steam, right click on fnv, then properties, then verify local cache. It sounds like there is glitch in the program and doesn't knoe what to do, so it quits. If that doesn't work, install nvse, script editor, it has load log that can help pinpoint problems. Also try launching the game with nvse. Launching with steam failed me so many times that don't use anymore. Than tell what happens and maybe post the load log.