How exactly does polyphony work?

[ForAiur]

I have 3 uPlaits that have their own lowpass gate, or I can play them paraphonically through one filter. I also would have 4-6 envelopes of the same type, so it could work. But paraphony would be enough for me, I just need polyphonic recording.

I only spent like 4 hours alltogether with the NerdSeq (baby son) ... so sorry for the beginner questions (but I read a decent size of the manual). A midi track is something else than a normal track? I want to input it with midi but control it with CV

Currently this would work with the CV16 expander since it is the only one with multiple outputs within 1 track.
It is not possible right now with a plain nerdseq except for within a Midi track.

I have both expanders. So I can set it up to record up to 4 notes into a single track? how does NerdSeq then show 3 notes in the same spot in the column?