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.
Man I had no idea complex music like this was possible to port into SMW. This is too good! I had to compare it to the original version, and it seems like some echo effects and background synths are notably missing, but it's impressive how close this is to the original. I'm guessing the samples were recreated from scratch? The percussion samples sound a little different, but the lead synth sounds ripped from the original song.