All is clear and working as intended. Many thanks everyone!

All is clear and working as intended.

You may want to both bookmark this thread and copy it to your computer. Sometimes links get lost or broken and you can't find the thread anymore.

I also suggest you reread Bad Mister's replies. There is a LOT of detailed explanation in them that you won't find well documented anywhere else.

His replies explain how the functionality is designed to be used. You certainly may have found a different way that works (not using zones for the parts you play) for this one particular use case.

But when you later begin recording or using a DAW you would suddenly find your MIDI flooded with info from those parts and not know how to fix that problem.

If, instead, you do it the way Bad Mister advised (even if this use case doesn't require it) it will work properly no matter what you do later.