To get the full functionality including elevation and course warnings you should take your Strava route and then import it into BikeRouteToaster, then do an export to tcx. Then put this file in the 'NewFiles' directory on the 520.
Thanks for the replies. I use a Strava TCX file today and got a route marked on the map that i needed to visually follow as no cues. I didn't look at elevation. I will try what you suggest next time