unfortunately i cannot write/take the time to learn JS personally
but i'm a very good tester and would lend considerable energy into this initiative
here is my "monome" ... it is a set of tracks/midi fx in REAPER that turns a launchpad into an MLR style monome emulation. it relies on the excellent Piz Midi Looper.
in performance, i will always be playing to a backing track to which my quantise settings will be locked. it will be harder to keep 4+ patterns in time all together if they're struck without any tc...though i guess that's the ultimate goal in monome dexterity
http://youtu.be/zwXLBg67hK4