This may or may not be a bug. I just did a new install of v1.2 . Everything was working fine. I added a couple of resources and about five or six forums. Then I added a label and it inserted a label fine. I then used the "move" feature to move the label to the beginning of the forums group and when I did it locked me out of my site. As near as I can tell right now it was caused by moving a label but I'm not sure.
This should have been posted in bugs, right? I had a hard time finding it . Sorry!
I found a quirky temporary "fix". If I change the language I am returned to a logged in state. I can then select and return to my original language and everything continues as normal.