Impressive port so far. I did notice a few things tho.
For controls, attacking on the ground makes you unable to jump for a certain amount of frames. The original allows you to jump at any point in the attacking animation, so this feels really bad imo. You try to throw and jump at the same time and you are just stuck on the ground as it eats your jump.
And similar, if you are moving and you attack and jump on the same frame, you will not attack.
A couple glitches in this clip. An enemy sprite got stuck floating in the air on the first screen.
And you can skip the first boss by having him hit you into the door.