I can't get the midi sync to work between the JP-8080 and Rebirth...

I'm using cakewalk professional and it works great... I send the start/stop/position data on the same channel as the instrument and make sure the control channel on the jp8080 is set to recieve on this channel (it defaults to 16 or something, even though your instruments default to 1 and 2). Then you also need to enable the sync feature you want to use (delay, RPS, etc.)