"plan the route" as in get the Nav computer to calculate the route to your destination.

The Roue Magnet option is on the 'popup' type menu that you get if you press the right hand knob while viewing the map while guidence is active. It's only available whne in Euro mode. The way you select a 'magnet' is the same as the way the 'Destination Input Map' works, you move a cursor to a location and the store that location.