Mega Man 42 is a Mega Man fan game, made with Game Maker 8.1. Dr. Wily has kidnapped Beat, Rush and Eddie. It's up to Mega Man and Roll to save them! In their way stand eight new fearsome Robot Masters: Sand Man, Art Man, Ombuds Man, Zombie Man, Missile Man, Mad Man, Sky Man and Brain Man.
I've made a video where I compare the jump in the game side-by-side to the jump in Mega Man 1. When you look at the video, have in mind that there are people out there who take it as a personal insult that the jump doesn't work exactly like in the commercial Mega Man games. If that isn't worrying, I don't know what is.
Even though I tried to get the jump as close to the real thing as possible, I'm not a perfect person and it IS a little bit flawed. I have a list of bugs and other things to correct for version 1.1, and the jump is high on that list. I want to make a point though, that in my opinion you can still enjoy the game for what it is even though it's not completely true to the commercial games. Point in case: The Gameboy Mega Man games.
The GB Mega Man games' physics engine and jump is completely different from the NES games, but they are still very enjoyable. I recently bought all five on Ebay and played them through. If you count out MM42 on the principle that the jump is faulty, you should also count out the GB games, in which case I think it's just your loss. Furthermore, another fan game called Mega Man Rocks has a jump that isn't anywhere near the commercial games, you jump way too high. But it's still a fine game, and an accepted fan game.
I'm sure this post will not make the critics silence their voices, but at least you have my stance on this debacle. Enjoy the game for what it is, if perfect replication is what you're out for, play another game. I was going to say "play another fan game", but there is no such thing as a fan game that plays exactly like the real Mega Man games.