Not bad as hack,good level design even if is too easy for who has completed the original Mario World...and the OST remix of Mario Land 1 is outstanding!But in the water level,and in the castle level...is soooo horrible the OST;in particular on the last one,that OST get much more worse all the things up...with original Castle theme,that could be a great castle level,for me.
For next hack,I expect good things from you,you have some potential as hack level creator^^
I don't have anything to say about - it's about as basic as can be. The only thing I'd like to point out is that you shouldn't use red level dots for levels that don't have secret exits. I get that you used it because it look like lava, but everyone will interpret that as having a secret exit. Likewise, please use red dots for levels that DO have secret exits. No one's gonna look for secret exits in yellow-dot levels.