I tried separating My Trails into tracks. In order for the tracks to show on my Garmin map screen, I have to go into Track Manager and turn on Show on Map for them one at a time. Kinda tedious. Is there no option to turn on that property before they are downloaded from BaseCamp to the device?
No, this must be done on the GPSr, and keep in mind that each GPSr has a finite limit to the number of tracks that can be enabled to show on map at any given time.