I just wanted to say thanks for your efforts on this project. I've been looking for something like this for a long time. I'm keeping my fingers crossed that you'll continue work on it - this is one project I'd be disappointed to see abandoned.
I haven't gotten a chance to poke through the source yet, but I've been tinkering with the designer application and examining the generated XML. I can already tell that this will be a great asset and lends itself well to end-user UI customization.
Very cool stuff. Good luck and keep up the good work.