I've got this head unit with in built sat nav on my SE TD4

Is there a way of adding a usb port so we can plug in a usb stick and play music off that as an aux ???

There is no USB connection on my MY10 HSE (same head unit) I use the aux socket at the rear of the centre console. Connect your ipod or MP3 player and power it from the adjacent 12v socket. A little basic but it works.
Bob 10MY (Sept 09) TD4 HSE Auto in Stornoway Grey (Now Gone)

08 FL2 TD4 SE Manual in Rimini Red (Now Gone)