Dynamic routing option will only work if you have the very latest BM54 tuner module fitted. I am not sure when in 2006 this tuner was introduced, but will probably depend on the build date of your vehicle.

I know this as my old-style BM54 went u/s and the dealer replaced it with the latest version - Dynamic Routing magically appeared on the Route Selection menu.

You know, the 'old' BM54 tuners aren't too reliable - They do go wrong from time to time and the dealer will swap it out under warranty for the latest version. Mine was intermittent - sometimes the radio would not come on and needed a 'key off, wait 5 mins' lark. Only happened once in 10 trips, but it was enough to get the dealer to swap the radio.

Of course, if you bought the car with the belief that Dynamic Routing was an installed option (due to the sales brochure) and it isn't, then report THAT as a fault and get them to sort it