Applaud the efforts. Motion/gesture libraries in general are notoriously tricky to get right.
I am a little bit confused at the three gestures you chose in terms of 'launching' with. Recording custom motions and a good path to implement those could be incredibly useful, but I'm a little bit hesitant at the real world use of the 'knock' and 'backtap'.
Either way, signed up. Keen.
The use of backgrounds in that website make it a little bit hard to read stuff, by the way :)
What are the plans long-term for this?