I see If I can add looping..
I can add so .mid files are sent to the MediaEngine. But if something is actually playing or not is not up to MC. Playing audio is handled by Windows. So it depends on what codecs is installed in Windows.
Alright, thank you —that'd be excellent ! Ideally, Looping should be configured via a checkbox setting in either Core Settings or Explorer Panel Settings (whichever, I get confused.) Also, .MID should be played —I'am not 100% certain though.

P.S: You can test /w this .MID (MIDI) audio file (they are all generally very tiny file-sized):
BSQ.MID (36 KB)