Using the downpatcher I went from 1.6.9 to 1.6.3, then 1.6.3 to 1.1.30, everything works fine and runs fine up until I leave the vault and it loads into the commonwealth and your character shields their eyes, just after when you regain control the game crashes to desktop, no message or anything. I've tried running it in every compatibility mode and nothing has worked and I can't find anything on this. Any help?

You could try some of the stuff here: http://steamcommunity.com/app/377160/discussions/0/496880503080272491/

I've gone through that list and tried everything, I don't think it's a graphics thing, I have control for a second then it just crashes straight to desktop,

Try verify integrity of game cache, and then downpatch again. Sometimes the game can bug out from the downpatcher.