Hi all, thanks for the info.
The problem was, I didn't have the DR-880 drivers installed. Recently formatted my hard drive and simply didn't re-install after the OS install.
So, onto another question then. I'm getting my MIDI input now, I can see the MIDI data in the MIDI track after recording.
Can I record a MIDI session (as I just did) and then apply my Ez Drummer software onto that? I've been poking around but not seeing anything that looks obvious on how to do it.