Thanks for letting me know about the issue on Vive! I'm going to upload another version today that will hopefully fix the issue. I wish there was a simple solution for all the different headsets.
It depends on your definition of "gameplay". There is interaction - it tracks your hands movements and procedurally creates the music. Also a few special motions play percussive instruments. There is no win or loose state, which is quite typical in my games. :)