Hi there,
If this works anything like Pa50, in Style Play mode you choose Full Upper keyboard mode, choose the sound you want to use, lets say Piano, mute all the accomp tracks except for drums and perc.
There you are...
I for instance assigned the pad buttons to mute/unmute drums, bass, accomp and left and that really provides an easy way to control the accomp instruments. I don't know if that is possible in KMA, try it.
_________________________
Yamaha S770, Studio One 3, EMU 0404USB, ESI, ATH, Dell. And others.