davidcurryuk,

Overlay data is stored as default by Memory-MAp in the DOCUMENTS > MAP OVERLAYS folder.
You should see userdata x .mmo (you may however have more than one file)
If you double click on this file, the overlay data from your back-up will load.

Thanks

Thanks a lot, I'm away from base camp at the moment, but will look at it in about a week from now.

Thanks for the info - the route files are precisely where you said, and I'm back on track.
I think this item can be closed off.