When not having a key bound, this add-on used to throw an error upon opening the guild window.
I added a quick check for that, and the problem is gone.
Thanks for the hint Next time better write me a PM and we can fix it directly in the addon.
I'll have a look at your code fix and implement it later on.
Edit:
Found your code line and will add it into the next release.
Thanks for the fix manavortex!