Question #1, Expand Sequencer Memory?: I have an XS8.  Does adding memory expansion boards (I think intended for audio sound sampling) also expand MIDI sequencer memory?  (I need more MIDI sequencer memory in Song Mode.)

Question #2, Effects in Song Mode?: Other than the effects already inherent in the Preset voices, can I add effects to a song in Song Mode?  (I’d like to add effects, but can’t figure out how to do it.  Edit mode only seems to allow me to edit MIDI events and choice of voices, not effects “inserts”.)

Question #3, Save Mute with Song Mode?: I’ve recorded several tracks for a song in Song Mode, but want to normally play along with the other tracks while muting the 1 track I want to play “live”.  Is there a way to Save with the song the fact that, when I call a song up, the track of my choice is already muted whenever I call up that song?  (So I don’t have to actually mute the track each time I call up the song.  I keep storing / saving it, but the track is no longer muted when I call it up the next time.)

Question #1, Expand Sequencer Memory?

No. There is no way to expand the sequencer memory beyond the resident 1024KB. You can however, load individual SONG files from your USB stick. Individual SONGs or sets of SONGs can be loaded in seconds.

Question #2, Effects in Song Mode?

No, other than the 8 PARTS recalling there dual Insertion Effects, the Reverb Send and Chorus send from each of the 16 PARTS, the 3-band EQ per PART, and the MASTER EFFECT and 5-band MASTER EQ, that’s it. :=)

Insertion Effects can be customized on a per SONG/PATTERN MIXING setup.
Press [MIXING]
On the mixer you can place a red check mark next to any 8 PARTS to activate the INS FX SW (Insertion Effect Switch)
For any PART with the INS FX SW active when you press [VCE ED] to drop into full edit on that PART, you will be able to assign any two INSERTION EFFECTS to that PART.
Press [STORE] to create a new MIX VOICE created especially for the current SONG or PATTERN. (so you do not have to use the same effects on a VOICE as it is stored in VOICE mode, you can customize it for each SONG and each PATTERN MIXING setup!)

One very important thing to know about the XS: When you press [SONG] and then press [EDIT] or [JOB] - you will be editing MIDI Events on the Track or selecting jobs to edit the MIDI Events on the Track.

When you are press [SONG] and additionally press [MIXING] - MIXING refers to the Tone Generator of the Motif XS. It is the synthesizer. So if [MIXING] is lit when you press [EDIT], you will be editiing parameters that affect the sounds (this is where you would find Effects, for example), if you press [JOB] you will be editing somthing about the synthesizer engine.

Question #3, Save Mute with Song Mode?

TRACK MUTE status can be recorded to the SCENE Track of the sequencer. You can create as many TRACK MUTE Events as you require. TRACK MUTE EVENTS can be recorded in real time or they can be entered into the SCENE Track using the EDIT function.

From the SONG screen:
Press [EDIT] to view the EVENT LIST
Press [F4] TRACK SEL (Track Select)
This is a three way toggle that will select a Numbered Track, or the SCENE Track or the TEMPO Track.
The SCENE Track can have two types of event: SCENE MEMORY Event or TRACK MUTE Events.
Select the EVENT TYPE = TRACK MUTE
Use the numbered buttons [1]-[16] to activate and deactivate tracks as necessary.

Scenes and Track Mutes explained

Thank you, Mr. McClendinnin, greatly appreciated!