It would have been even better if Garmin had made courses compatible with the concept of 'saved tracks.' There's really nothing new going on in a course.
Happily, Garmin finally released the specs on the new units, so course support is a possibility. I'll add it to the 'todo' list. Thanks.
Glad to know there's a workaround in the interim.
You can definitely merge tracks from the main window -- the profile tool doubles as a merge tool. Just hold down shift between clicks, and when you are done (you can reverse direction, too), right click and choose "save as..."