ALRIGHTY! I was finally able to reproduce the crashing bug for a few tries, and I have it narrowed down to a particular section of the code (the quest objectives capturing). I still have no idea WHY it's causing problems, but it is. I have an artificial prevention for infinite loop in that section but it still freaks out. Ultimately, I don't know of the WoW client likes reading the Quest info upon load, so I've removed the Quest capturing from the "ADDON_LOADED" event trigger. Instead, I've put the quest capturing in the /gbk command as well as when certain quest aspects update (like when a quest objective gets updated).
Unfortunately, half-way through working on this, the mod stopped crashing on me again, and I had to resort AGAIN to guesswork.
Hopefully this new version works properly for everyone: 0.42
http://www.dkpsystem.com/files/GuildBank.zipBeautiful! You rock Chops!
Thanks!