Waypoint on SatNav

[Red L Driving School]

Hi, I've got a 66 plate Prestige DS3 Cabrio with the touchscreen SatNav. I'm trying to figure out how to add a waypoint to the destination, I'm a driving instructor and want to be able to make the car route certain ways to a destination for my students. It has waypoint as an option in the handbook, but on the screen in the car the waypoint option is greyed out. When I enter a destination, the waypoint option just doesn't do anything when I touch it. Does anyone know if this option is useable on U.K. spec cars? Thanks.