I've had 2 users with problems editing signatures. I think I have fixed that issue so if you meet the 5 post criteria you should be able to edit your signature. I want to start this thread to see if anyone else is missing any permissions. Is there parts of the site you could access before that you no longer can? Can you edit you profile, sig, post status updates? Is there anything not working permission wise like it did when the site ran vbulletin? Let me know and I'll look into it.
I can do everything save for edit my signature, as before. Going directly to the page gives me the #1024 error code.