Small point regarding the demo-- I love that it's open and really gives you a feel for the entire product, but you might want to consider making an editable, disposable session for each time someone logs in. For example, one of the assignments I saw was "testicle1", which I doubt you put in, and may put off potential users. Instead of controlling for that sort of input, I'd just have a default recurring demo screen that is editable but not saveable, and gets destroyed once you end your demo session.