Managing Waypoints on the Quest?

[Ekke]

Am I missing something on how to work with Mapsource? It seems easy enough to download waypoints and routes and things into the Quest but erasing them from the GPS is another ballgame. What I'm doing now is deleting old waypoints manually from the GPS. Surely it must be possible to delete a whole whack of them using Mapsource? Something like an MP3 player that shows all the files on the unit and then you can add or delete files as you see fit from the PC.

Any and all help appreciated!