Email Yamaha (or Google for them) to get the IR codes for the DVD player. They should be able to provide you with a PDF. I did the same for my RX-V2700 receiver. You may also want to check remote central's discrete hunter for your DVD player.

Once you obtain the PDF with the IR codes, send them to Harmony support and they will add them to the database.

Expect about 3-5 days response from Yamaha and 2-3 days response from Harmony. Be patient. It took me a few emails to get the document from Yamaha (they sent me the wrong stuff initially) and Harmony will only add the codes that you specify, so be specific as to what you want. If you only need the SKIP button, that should be easy. If you need 12 commands, list them.

Good luck!