Now that I know routes cannot be transferred using the workflow below I use BC "Create a Track from Selected Route" to create a track and include it in the Export.
I like to use a big desktop screen and BaseCamp using the various maps I have installed to create route, track and waypoint content, then Export and copy the gpx file to my phone, then use the Explore and Drive apps on my phone to transfer content to the Zumo. Note: the route created in BC shows up in the Explore app but does not get sent to Zumo
Then on the Zumo I go to Tracks and convert the track to a Trip which then shows up in the Trip Planner and can be run as a route with turn by turn directions... I have Off-Route Recalculation turned off
Everything now works as it should on the Zumo...I have a track, a Trip (route converted from the track) and waypoints that don't lose their icon image as assigned in BC in the transfer
screen shots: left side BaseCamp...right side phone Explore app
screenshots from Zumo Explore <All>
and Trip Planner