How do I go about setting up media keys (pause, play, next track, previous track, volume up, volume down, etc)
Download and go to page 53 of the HID Usage Table. There you will see all of the HID Codes available for use with the Twiddler. Keyboard Usage (0x07) page.
HID 127 MuteHID 128 Volume UpHID 129 Volume Down
That's it, for now.
Great, thanks for the help