Sweet!
Looks like a good start. I'd suggest instead of the large text boxes explaining how to do things, put that in tooltips or a closeable help section, and have, for example in the resources section, a display of the resource in a box. You probably have that idea already.
I suppose you'd get a quick boost if you were to have my data structures for the skin-related stuff. I can provide you the classes, but they're c++ and need to have an environment where you can use libxml2, and templates. Would those help you at all?