In the admin panel when adding a large number of subcategories it becomes impossible to edit or delete the lower list. This window should be scrollable, movable, resizable, or have multi-columns for this. I have tried this on IE8, FF3, Chrome, and Opera all with all bars closed and my screen resolution set to impossible to read to get to the lower items and still couldn't. The lower bar was open during the screenshot but was set for autoclose. Didn't help much.
Check out screenshot:
Also would like to mention that my age limit was set below 18 years old in the admin but was unable to join as error message popped up in join form. Sounds like an easy fix but thought I'd bring it up for a bug free release.
And last, but not least I am unable to get any modules working in the OpenSocial module. Could be I know nothing about it but it looks like it should be simple. I've tried versions from all the opensocial.org directory with no luck. I have three complete beta 5 programs running and get the same results from all. One is hosted on Linux, one is on my production LAMP server, and one on a production Windows server.