Although it's been a couple of years since I last used polychain, as far as I remember, if you connect the MIDI cable and set the globals correctly, everything should be doubled and controlled by the master instrument. But my personal preference has been to treat the keyboard and module as separate instruments that are simply MIDI connected using the In/Out jacks, rather than polychained. I would use polychain only if I specifically wanted a sixteen-voice instrument. The non-polychain method gives you a stereo field (by panning at the mixer) without the complications of the Output B arrangement, and it allows bi-timbrally whenever necessary. It's simple enough to use, and is more flexible because each instrument remains independent of the other.