The Oopsie Fix!
In the last build, and it might have been happening far longer than that, when opening a single player instance your client would crash. Ok ok, I've come to the conclusion that this is being caused by a corrupted quest database that start when when of my team members began working on redesigning the quests but gave up on it.
It was the quest database that was corrupt. The fix worked and we are even booting 2x faster than before.
Thanks again to Chaz and Wooly for being patient and talking like sane people.