Oops! Almost forgot. If you are going to change the channel start number, also change it in this procedure:
scanExpressionPedal()
and this line
Serial.write (0xB0); //controller (channel 1)
e.g. Serial.write (0xB1); //controller (channel 2)
changes the starting channel from 1 to 2.
Came across Sowa's boards in a small four rank pipe organ once. Very nicely engineered. I was impressed.