v1.10: Quick Look support
A Quick Look extension has been added, allowing MIDI files to be played directly from the Finder, and from file dialogs. This version requires macOS 12 (Monterey) or later. (The app is otherwise identical to v.1.05.)
Due to a skills shortage, it's a fairly minimal implementation. Note that you need to press the Play button to start the preview -- this is so that files don't immediately play when they are selected in the Finder.
The code works well: but there are a few interface issues that need tidying up. If there are any problems with Quick Look, you can delete the qlMIDI.appex bundle from inside the app's package > PlugIns folder.