You may be thinking about the "StyleMaker". You can use the StyleMaker to create a new MIDI style or edit an existing MIDI style.
Thank you, Jim. That's not something I've explored before. Didn't think a MIDI only style would have associated RT but maybe this one does, because BIAB offered to substitute RT for it. I just thought that was a standard dialogue for all MIDI styles. Still have so much to learn!