Movement feels nice, and I didn't encounter any game breaking bugs. On the 2nd playthrough I attempted to look for bugs.
I could walk over these gaps with the yellow enemies before the flagpole in map 1.
If I shoot one of those circle enemies near a wall, it gets stuck. In addition to that, if an enemy was stuck in the wall there, if I respawn at that checkpoint, I would get hit immediately.
Shooting on a moving platform (Horizontal at least) makes the grill ignore the carry speed of the platform for a few frames.
(After boss) I went back to the flagpole before the boss, and one circle enemy was stuck in the ground about halfway.
And some minor nitpicks that might not be bugs:
Going on a spring then immediately jumping resets your vertical speed.
I kind of expected to bounce higher off of enemies by holding jump, but it doesn't appear to do that.
Looking great so far though. I also probably spent about a minute trying to get the options menu to work.