In Windows, I can right click on a MIDI file and select Open With … Cubase. No problems (other than seeing a dialog box asking what directory I need to be in).
But when running Cubase, even with no projects open, File/Open will not accept a MIDI file as a valid selection.
If I can do it in one place, it seems I should be able to do it in both places. Any reason why things don’t work this way?