All I can say is Marvelapp is the shit! And I never thought I’d say this, but my experience with Adobe Captivate was very helpful here. Putting this together with Marvelapp was really no different than building a branching, self-directed training.
App Prototype
The awesome Marvelapp’s website

note: I edited this post on March 20, 2014 to reflect the prototype should be working now, and removed the (mostly) from the posts title.