[kftgr]

There are registry setting for S2P itself that govern rotation.

HCKU\Software\A_C\S2P\

From the readme:
- ShakeAction - for some HTC devices only; 0 to disable; 1 to go to next song; 2 to go to next shuffle song.
- ShakeThreshold - for some HTC devices only; responseness to the ShakeAction; 0 easiest; 200 hardest; default is 100.

BTW, version 0.80 beta just got released that has a settings menu for these items.