Ok... after reading through the forum (which is awesome) last night for a couple of hours I think I figured it out...
1. Set the first DP-415 to read channel 1
2. Set the second DP-415 to start reading at channel 5
3. Set the first group (Back wash) of Color Wash light to read channel 9 (Master/Slave mode)
4. Set the second group (Back lights) of Color Wash lights to read channel 13 (Also Master/Slave mode)
Is this right? Am I even close?