Thanks for that, Frankie. I used gpsbabel with the ‘msroute’ input file option to convert the .axe file to a gpx one, but it only contained the start/stop routepoints. I don’t have Mapsource, so can’t test the final part of your suggestion. However, I was hoping to be able to use the track I’d tweaked and finalised in AutoRoute without having to re-do parts of it in another application.
As a matter of interest, which track-plotting software works well? I’ve used some of the free Google-based ones (Marengo for planning ‘direct’ routes, and Bikely for road-following tracks). Bikely would be fine, but it’s extremely slow, and if it takes a wrong turn then deleting all the track points is a job and a half!