This is really cool, perhaps this means I don't have to actually read PM --- it's still staring at me, unread, from the book shelf --- or at least not up to *56 . Do you use this in your teaching? I think it would be cool for students who have courses on either PM or subjects related to it to have this as a resource in their syllabus.
Also, I don't know if there's a problem with my web browser (I tried it with Safari) but I did get some "Unexpected errors" from time to time and had to restart the game in order to continue.