John.....first off sounds like you want to turn the sx900 into a
Kn unit which it is not?
Can you please be more specific as to what you actually want to do setting up the KB as reading this makes it a bit confusing ....changing styles within one song? etc....
You can easily go into the Mixer menu and go to style parts
"OCTAVE" and change each part there
and re save the Reg, OTS, sounds, etc, for the song..
trying to help but need to know more on each question.