http://www.youtube.com/watch?v=vZaRgMOo-IgIF someone wanted to, this looks like it could be scrolled with layers of plywood. After watching a few times, stop it on the 10 second mark for a fairly good view. It appears that the left side of the track is high. A channel for each size coin, with the channel for the next bigger diameter raised above the last. The quarter doesn't fit any. It follows the high left side & the right side goes up over everything.
Post a picture when you are done along with pictures of all the designer firewood you created trying to get it to work.
I will pretend to be too busy to tackle it.