Jon (in CT) had it exaclty right the only thing you need to connect to the NAV display are video to the top right of the Molex and shield/ground to the bottom left. You can leave the rest of them off. I hooked another cable up to the RCA jack on the NAV and also to the top left and bottom right of the NAV molex just in case I needed them later. I just didn't want to take the dash apart again if I found out how to get the NAV to display video from the RCA jack. No dice so far.
I ran the video cable down from the dash to under the driver's seat, then picked up switched power and ground from the wires going in to the DVD unit - hooked everything to one 4 wire cable which I just got finished running under the carpet under the 2nd and 3rd row seats, to the right back corner of the car, up the back corner, through the little rubber bellows thingy to the hatchback, down the inside of the hatchback, out of the square hole hidden by the black plastic strip that houses the 2 license plate lights, and down to the camera mounted on the license plate frame. If you do this, I would suggest wearing some gloves or you will need some neosporin and band aids. Also an electricians fishtape is vital.
You could just run the video cable back to the camera and power it with the reverse light wires. The way I did it, my camera will be powered up whenever the car is on.
Hope this helps.