Radium Music Editor

This could be what I am looking for...

But in general use it feels slow and very unstable. I tried on Windows, as that was 'recommended'

I tried this with some of my own OctaMED files, and the experience has been ... well ... not pleasant. None of them load.

Note: I used MED, OctaMED 4, OctaMED SoundStudio, Protracker, before moving to Renoise, Reaper and Bitwig. Also used Samplitude and Sonar for a long time. Amiga user with a large collection of modules and samples I created over the decades. I like trackers and hate pianorolls. I like the Korg Gadget interface, but want a tracker for MIDI.

>but want a tracker for MIDI.

Renoise is probably your best option for a midi tracker, Radium (and most trackers) are meant to be stand alone and they always seem to have issues or irritating limitations when it comes to midi.

Have you ever found anything which loads & plays *MED files properly? Specifically MMD2 format files from SoundStudio. I've also got loads I created back in the Amiga days, and I've still got SS itself running on an old laptop but would prefer something that could play/render them to WAV on macOS.

I had a Windows version of SoundStudio, but can now only find the demo. Lost my copy a long time ago, so not really. I use emulation, like WinUAE/FS-UAE for this.

Playback can also be done with something like uade, but terminal only.