Tip: Layer 3 backgrounds and tides disappear when you hit a message box, so plan your level around that. For example, you can add a sublevel without layer 3 at the start/midpoint, and include your message there.
Very nice puzzle hack with a lot of creative elements. Only issue is that there is a message box in room 2 that just gives a blank screen with no words. I saw from the solution video that it should actually have a clue for how to finish the room. Without the clue, the puzzle is essentially impossible to solve. I'm guessing this is a glitch resulting from some change in v1.2 but not really sure.
It's possible in many place to cheese the puzzles with mechanics abuse like gatehacks and perfect flutters, but just keep in mind that these are never the intended solution.
Also, in response to Shiny's comment, the first password is revealed in the game (I won't give any more information than that to avoid spoilers).
This is a masterpiece.
Although I don't like so much the puzzles (even less in YI where they can be annoying) they are very, VERY well designed in this level. Some of them were almost the same (I mean, using a sequence of melon(s)->P-switch->Red Platforms or in other order) but there was always a detail that gave them a special vibe and gameplay. You did an awesome job with tilesets and palettes too, some of them were very pleasant aesthetically (like Door 5 ) and if that wasn't enough, there was also FUCKING AWESOME custom music that really is very well done for contributing the hack's theme.
The only negative point (and honestly the reason why I'm giving this 4 stars instead of 5) is that is literally imposible to reach 100% without knowing (at least) the very first password, which seems to not being knowable by purely playing the hack (at least as far as I know, let me know if I'm wrong), forcing you to recur to "third-party" sources.