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.
Reminds me of Jimmy52905's scrolling in his Ice World hack. I did not believe it was a Super Mario World hack at the time because of this smooth panning. It makes me think it was Game Maker, but I am happy that you are able to create that as well!