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.
The song as a whole seemed spot on but the instrumentation could use a little work, it was very iffy and abrupt. Your SPC ID666 tags also weren't edited so please fix those if you can.
I took a look at your txt file too and there were a few unlooped passages like rests.
Turn passages like ...
Code
r1^1^1^1^1^1^1^1^1^1^1^1
into...
Code
[r1]12
...that will ensure the smallest possible insert size.
1 
