I saw an earlier response from Laff's that's he's aware of the problem of not being able to right-click the upper spell bar to disable a spell, but I thought I'd relate a somewhat humorous effect of this:
Several days ago, I cast Summon Zygomid to create a little mushroom pet (you get it in splitpaw arena). Later on when I wanted to get rid of the rascal, I found I couldn't! The spell doesn't appear on the lower spellbar, nor does it appear in the maintained spells bar, only in the upper bar where you can't turn it off.
The little booger follows you around EVERYWHERE and doesn't disappear on its own, so he's still following me around 5 days later! lol!
It's not a big deal, just kinda funny.
I'm also experiencing the same problem as Krylosis with the petition window -- items are black. And I also can't seem to click in the text box in the friends window either. I have to add / remove friends w/ commands. (ie. /friend).
BTW, very nice interface, Laff's, thank you very much for it! I think I speak for us all when I say we appreciate your hard work.