To Enable DVD Player during drive mode, you can follow there steps
#1 : Check and make sure that you have an USB stick drive, formatted with FAT32
#2 : Download from this link
http://bit.ly/1PIiCgr
Unzip and copy all files (but not include the folder - i.e: enable-dvd-and-touch-screen-tweak) from the unzipped file to the root folder of your USB drive
#3 : Turn OFF you car, plug the USB drive to USB port of the car, Turn ON your car, waiting for 20-30s until you can see 2 dialog messages on the screen.
#4 : Turn OFF you car, remove USB drive from the hub. Turn ON you car. Now you can insert a DVD -> play -> drive to see the result.
IMPORTANT: You need to clear all files from the USB after this final step - nor it will "root" the dvd feature one again for next using of the drive
P/S: Working well with OS version 33 and 55. Some reports that v51 doesn't work!