The R300 is a finicky printer when it comes to printing on CD's, I know, I actually look after 7 of the damned things in work!
Anyways, to get your printer working on the CD tray, it is *essential* you get the white arrows lined up initially. Once you start the printing process, for whatever bizarre reason, yes, the rollers go backwards, spitting the tray out a little bit, therefore not being able to bring the tray back in. What you need to do is while it's performing this short backwards run is to gently hold the tray from moving. Hardly ideal solution I know, but at least the printer will then take the tray into the machine, calibrate off the big white blocks and then carry on printing.
There might be a firmware and/or driver update for this problem, I've never got around to looking...
Good luck!
Jason Aspinall, September 2007
