1. When inserting, check that "Enable MIDI Output" is checked
2. Set Synth MIDI track Input to Cales output, enable permanent echo on this track
3. focus Cales MIDI track and play
(I have just checked that it works, removed it after... my own MIDI plug-in with which I manipulate MIDI is 20 times smaller and does not require "super" routing. But I have to "program" scales myself

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