I’m trying to setup my XS with an external controller (an old Alesis QS that is multitimbral and can transmit on multiple midi channels simultaneously).  I’d like to use the XS in pattern/master mode as my sole tone generator.  I’d also like to avoid having to send program changes to the QS to change layer/split points for each song in the set. 

My thought is that if I set the QS to send channels 5-9, I could use the Master mode to Zone channels 1-4 off the XS keyboard and then Zone channels 5-9 off the QS.  I’m having a beast of a time figuring out exactly how to set up the XS to do this.  I expect this has been asked and answered before - - can anyone point me in the right direction?

Hmm - let me make this simpler.  I want to use Master Mode to define, say, up to 4 zones that are driven by the XS’ keyboard and the other 4 zones driven by an external midi controller.  All zones use the XS tone generators.  I dont want to send new split / channel definitions to the external controller with each program change - - I would rather have it just send everything on, say, channel 5 or channels 5-9.  Is this possible and how?

“I’m trying to setup my XS with an external controller...”

Then you do not want to use the Motif XS in MASTER mode, you clearly want to use the Motif XS as a slave not a MASTER. Make sense?

What you want to do is setup a MIXING setup (either SONG MIXING or PATTERN MIXING) - this is the mode where the Motif XS is multi-timbral. MASTER mode would be for addressing the Motif XS tone engine with the Motif XS as MASTER keyboard. So for now, FORGET MASTER mode.

Setup the sounds you want in a SONG MIXING or PATTERN MIXING program. Place the VOICES you want to use in PARTS 5-9. Set the NOTE LIMITS you require in the MIXING setup.
Press [SONG] or [PATTERN] and select a blank location
Press [MIXING]
Press [EDIT]
Press PART [5] - [9] to edit PART parameters
Press [F1] VOICE
Press [SF1] VOICE
Select your sounds use the parameters found here in MIXING mode to setup your splits (NOTE LIMITS), etc.

When complete. Name (COMMON EDIT > [F1] GENERAL) and [STORE] your MIXING setup.

The name “MASTER” in MASTER MODE is the clue that this mode is for when you use the Motif XS as your MASTER keyboard… as the Master is slave to no one.
Hope that helps.