Hi Mikef,
I have no knowledge of sequencing, so I can’t
help you with layering, hopefully some other
member can.

If I were playing a song with piano and drums,
I would put that in say memory one, and then
with piano on right one, and strings on right
two, adjust accordingly, and put in memory two,
so that when I played second time around, just
push memory two and you have piano and strings.

If you have a foot switch, you can move back and
forth as you wish, with out taking your hands off
the keyboard.

I am pleased, I was of some help.
Good luck with your project.
All the best,
Fred Wren