All is with the caveat that I'm pretty bad at platformers in general ^_^ I definitely found the mechanics interesting. I think the first couple levels were nice with the puzzles. The third level, however, saw me get "stuck" with arms on one side of an insurmountable barrier (which I was no doubt supposed to go the other direction to do something with *before* I jumped legs over the barrier to remove a future obstacle... but 'e couldn't get back since the return journey was too high for legs double-max-jump. I went looking for a reset of some sort, but since it's more a platformer than a puzzler, it had none.
I do wish that control would default to 1 (legs) instead of 2 (arms) when splitting, because most of the time that's what's required for progress. I also found myself wishing that the recombine didn't cause the character to surge forward (that sent me off the edge a couple of times XD )
I guess the only other thing, about the controls - I wish the "shoot" option had a keyboard alternative, since everything else was keyboard it would have been much more convenient for me.
I really liked the music and thought the visuals quite hung together well. Really great job! Thanks for the fun game ^_^ Cheers!