Hi Philippe,
As you have noticed the Montage posses some challenges for those who wish to work: "Just like the old days when I had a 16 track recorder."

That can be done, if you opt to chose Single Part programs, one per slot. However, if you would like to use Montage as your sound source, and take advantage of some of what's really new about Montage, multi Part, multi dimensional play, you will necessarily have to update that "old days" workflow. It's to be expected.

This may help... If you think of programs like "CFX + FM EP" as a featured sound in you composition, I think it will help. For example, the CFX acoustic piano in this Multi Part Performance is programmed with great detail - some 18 Elements that allow for lots of nuance and expression, particularly in the soft, medium soft, medium, and medium loud ranges, and of course the FM-X e.piano. If you select that sound as one of your main instruments or if you select it at all, think of it as a featured Part... One that might need some thought and planning to record into your DAW.

Just as you will ultimately have to make decisions on whether a track needs to rendered in mono or stereo, you will have to make decisions about the best way to proceed to record the combination of instruments you pick out. These are production decisions.

In order to record Multi Part Performances, you need to decide your best way to proceed. You could record, as in the old days - single Parts, then when you completely outline your composition, you can go back and replace certain MIDI Parts with the "featured" Multi Part Performances. You'll have the MIDI data, just send it to trigger the featured sound. Or simply add them last, as audio.

The audio routing will allow you great flexibility when rendering your MIDI tracks data to audio waveforms in your DAW. Obviously, when recording Multi Part Performances the requirements change dramatically. The rendering of audio routine will become a part of your workflow when working with Montage, simply because you will want to reuse your hardware.

There are dozens of workflows you can devise- find a comfortable one and work it.

Briefly, things you need to know:
_ You only need to record multiple MIDI channels of information to your DAW in the special case where your Multi Part Performance includes Arpeggio data that you need to document as MIDI events in the DAW. If, for example, your Multi Part Performance is a single instrument sound or a sound where there is no benefit to recording it to separate MIDI channels (no Arps involved), you should output the MIDI data on a single channel by setting the MIDI I/O mode to Single.

_ separate record templates exist for recording normal MIDI data, and for recording data that includes you playing and the arpeggiators playing other Parts at the same time. You must take responsibility for generating the right type of data stream, and set your DAW to record it properly.

The Montage's "MIDI I/O mode", setting is a critical "new" parameter to have a good handle on.

Again, in order to work as before, you need to work with 16 single Part programs... And You can. Simply record that way, building the tracks, render audio from them... then add/overdub your "featured" instrument sound(s) having freed the Montage for your Multi Part instruments.

If you'd rather mix methods (recommended), record the "CFX+ FM EP" to your DAW (MIDI I/O mode = Single). Freeze the audio (render it as a temporary audio track in your DAW, while keeping the Midi data muted in a folder...) now you can set your Montage to MIDI I/O mode = Multi, and work as in the old days... Thing is, once you recognize that rendering audio is a part of your workflow now, it's not an issue. Cubase's ability to deal with Midi and audio seamlessly is going to be showcase here. In fact whatever DAW you choose, you should be able to move between MIDI and audio data pretty smoothly. I find it not to bad at all... Especially with the DAW's ability to keep MIDI backups while using audio files to do the playback work (freeing the hardware to do other things).

If you need specific help, let us know.

Well that's a most excellent answer ! Thank you a million for the detailed description of things..
I'm going to experiment now.
Merci.