I just committed some major changes in svn on the 2.1 branch. You may want to hold off for a couple of days on getting latest. It will build but if you use any skin other than theblues1 it will be broken at run time.
I've been going through all the modules and pages and changing to CSS layout and now I need to go back through the other skins to fix them like I did with theblues1 skin. I should have things in better shape over the next few nights. I was going to wait until it was all working before checking it in but then again I hate to keep this much work checked out and another developer who is doing similar work in the 1.x branch needs to see my work.
Update 2/13/2006: I just commited at least enough fixes that you don't get runtime errors with any of the built in skins. Still the only usable one is theblues1 as the others all need some css work to fix the layout and style. I'll be working on those. If you have your own custom skin, you will need to get the 3 new Panels named divLeft, divCenter, and divRight and add them to your skin and then you will probably have to fix some style to get the layout right. There are some new classes for css, right now theblues1 css has all the right classes, you will need to get the missing ones and add them to your css and probably tweak them to fit your needs.