Another update:
Qtractor can be installed via Libertine (with libqtcore4 as prerequisite) and functions. Trouble is that Jack doesn't work and so actually recording on Qtractor hasn't happened for me yet. I think a real-time plugin is needed. I'm hoping someone who knows more than me will weigh in, but would this be useful to us?: https://ubuntu.com/engage/an-introduction-to-real-time-linux-part-i
Or does anyone know how to get Jack working with interface?
I will mess around with ALSA and see if I can get some MIDI stuff done.
Balrong