Well, it's a decent game, but it's got some problems. For reference, I completed the first part, but not the second.
First off, the lag makes it almost unplayable at times. It's minimal in the section where you pick up the projectile weapon, and at the beginning of Part 2, which leads me to believe you have too many things on screen or loaded at other points in the game. During the boss battle in particular, my game came to a standstill multiple times. I eventually got through by jumping on the boss instead of shooting; I take it that the cats were to blame.
I also found that there was a wall with no collision on it in Part 2, where you get the sword. I could go out pretty far left, but I didn't check right.
The controls as Dyno feel very stiff, especially the jumping. The jump should not reach max height every time you click the button; you should rise until the button is released, then begin to fall. There should also be a way to cancel the chicken or the jetpack early. The controls for Pallid felt more natural, though I'm not sure how that holds up later in Part 2; I only made it to the loopback point where you have to jump off of an enemy to pass a northwest arrow of coins on the left of the screen, but I couldn't figure out how to get enough height to get up there.
The art was a mixed bag. I would recommend giving Pallid's world a steel-blue, grey, or white colour pallet to match the background instead of the green of Dyno's, but that's just my personal opinion. The background for DynoWorld has a cool direction, but it could use some work; the clouds look very unnatural, and the moon has overlay issues with the stars and shadow.
The music was pretty good, but I would recommend trying to build an atmosphere in future games. In particular, the upbeat music in DynoWorld felt unfitting for the darker colour shemes. On the note of sound, I've found that if you stand in a 1-block tall space and hold jump, it spams the jump noise.
All in all, solid effort, but it could definitely use some fine tuning, especially to reduce lag.