I've been a fan of Megaman X games ever since. I tried making a fan game, but however, I failed. Take a look at it:
Megaman X: Velocity. The controls are great, you can play as X and Zero, but I refused to complete it(had lag problems). I don't have much resources either(bosses, new characters, osts... etc). This is why, it will be difficult for you to make a MMX fan game(
It took me 2 years in editing krw703's MMX engine, improving the physics, adding Zero, enemies.. etc). I'm not telling you to give up, I'm just telling you what I have experienced so far.
Anyway, I played your game(the one with Zero that is). The controls need to be improved, you need to add tiles, backgrounds, enemies... etc(I know it's WIP, but the game is pretty empty itself). However, I liked the health bar!