I was on a Chromebook with a touchscreen. Maybe you do "platform detection" and don't register touch handlers on laptops. I haven't looked at your code (I didn't see a repository link and I didn't bother looking further).
Cheers on the cool demos, I think it could be the start of a great resource for elementary school teachers introducing machines. I know this sort of thing would have been great when I was in grade 3.
