The github master is working great. However, there seems to be a problem with the admin theme. When I go to edit Options/Plugin, the plugin list is shifted off to the right, causing the horizontal scrollbar to appear, and making the edit process somewhat awkward. Apropos...
http://if12.mmax.com/my_data/sshot.zenp.bad_options.png
I checked Options/General, and the same problem occurs, although the offset is not as severe, since the properties input page wraps around to the currently active tab (and inserts the RSS tab on the next line down).
Firefox 11.0. I'll check it out in my other test browsers and let you know if it's browser specific. (Give me 5-minutes.)
Sorry about that. It's only doing this on Firefox 11.0. Should have checked that first. (It even worked fine on IE6!)