Is there any way to add music files to the hard drive while it's connected to my PC? I have about 1000 discs, and playing them all to record in the car will take the better part of the next administrations time in office. I'd like to just copy them onto the HD before putting it bad in the Z2 (upgraded to Z3). I'm not sure what format the avic software rips the CD's, or what type of file structure it uses.

No, and you can only put 400 albums on it anyway.