Seems this forum is a little quiet, dominated by the TR forum.
I’ve figured out part of this question myself - you have to go find the VCCDVDButton.exe file. Just search for it. Then you can select “Don’t use DVD button”. There’s a dropdown box below this are and it will let you do various functions with that “DVD” button.
HOWEVER, I’ve not figured out how to assign functions to the OTHER 4 buttons next to it.
Any info, please post back.