For each new arrangement, I try to think of a new way to build the instruments, use effects, and structure everything differently.
For #12, I was playing with the fade-in effect (4). Use different SPD values, you can change the speed of the fade-in. Instrument 0 is a 'one-hit' instrument:

Instrument 1 is a looped instrument with a volume tail. I used both of these to emulate the articulation of short and long notes at the piano.
