For the most part, this hack was decent, with nice aesthetics and musical selection, however, there are a few flaws I should mention.
1.) Some jumps are quite long for a first world, and some are even leaps of faith.
2.) The Mouser Boss has far too much HP, and seems a tad too difficult for a first boss. I was very close to running out of time by the time I beat him. Besides reducing his HP, you could try lowering the platform he's on a block or two so it's easier to get the bombs close enough to hit him.
3.) Boss victory music/Overworld music doesn't have #option tempoimmunity applied, causing their tempo to be faster if the timer was below 100s.
4.) Entering the pipe at the end of World 1 causes the game to crash, at least in snes9x.
So the original submission of this hack had a stolen overworld from this hack, that wasn't noticed by myself (who originally accepted this). This submission has a new overworld and an additional level which both seem to check out here.
Nonetheless, this will be accepted for now. If it turns out that this contains more stolen content, please contact a Hack mod to investigate the matter further.