Usually it will be a small m for minor, such as Bb7m. A dash in a chord notation doesn't ring any bells for me to mean anything musically. Just a separater between the letters and number in this case maybe.
*shrug*
I don't think the drums record to tracks....the drums just play along with whatever pattern or arrangement you have programmed, along with the audio from your recorded tracks. It is basically a built in drum machine.
http://cms.rolandus.com/assets/media/pdf/BR600WS02.pdf
I just looked at the manual, and there are only 2 inputs, so no real user defined routing...you are right. Armed tracks will record the inputs.
Have you read page 67 in the manual around Track Status?
Track routing would be assigning the inputs to the recording tracks....i.e. You set up 9 and 10 to record a stereo signal? Where is the input audio coming from for tracks 9 and 10? There would have to be some routing involved to get the audio signal to where you want it to go.
I am suggesting...
I would check your track routing and which tracks were armed to record. I would guess you had accidently set up tracks 1 and 2 to record the same inputs as tracks 9 and 10.
Can you replicate the problem, ensuring that tracks 1 and 2 are NOT set to record?
I am guessing user error here.
Is your bit length set to 16 or 24 in the R16? You need to be at 16 bits to have all 8 tracks available in interface mode. 24 bits is higher quality, but limits the interface to 2 output tracks to the computer.
You can find the setting under Projects -> Rec Setting -> Bit Length.
Are you using two microphones?
Edit - oops, never mind, I see you have the guitar going direct, plus a mic.
Sounds like a panning problem with the guitar. Pan it to the opposite side of the vocal mic.