The satnav software (which is no MkIII, IV or any other "legacy" system shared with earlier BMW-Land Rover models, it's a whole new touchscreen system manufactured by Denso) is updated along with the maps, you can't just update the system software without them. Basically, every time LR/Navteq release an updated map disc - about once per year or so - they also make small tweaks to the interface that are permanently and automatically uploaded into the system's firmware the very first time you insert the new disc in the DVD drive. You can order the latest data DVDs from Navteq's global web site: http://www.navigation.com/landrover
The 1791 "hack" code used to work on MY06s with original
map data discs to temporarily enable navigation on the move. The code has been disabled on MY07+ vehicles. As far as I know though, in Europe all "on-the-move" satnav restrictions were removed on 2007 and later models, if you own a 2006 I believe you can get a dealer to remove the restriction via a software upload (for a fee, probably.) Here in the US we still have to put up with the silly lockout when moving. If your car is a 2006 but doesn't allow navigation on the move after entering the hack code, perhaps the previous owner upgraded the map disc to a newer version already, and when doing so he inadvertently wiped out the 1791 code.