That a promising start! I wish you would finish this, 'cause this game was my first RPG ever, and seeing a full remake of it in this style would be awesome!
I really enjoyed playing it, even it's a little bit too short :D
I didn't encoutered the stairs bug like many seems to have. The experience was realively smooth once you get that running can be only only when you're standing not when you're walking.
I would love to see how celesto (not sure about the english name, I'm french and I always played this game in french) would render with all his double face level thing, as well as the comet battle, and some several cinematic. There's some pretty aestetic things to acomplish here!
As a said, a promising start! (Finish it, please! :D )