Make sure when you upgrade the map, the Map Display Name should be the same as you firstly named it.
Also when you upgrade and export it to CDW (Cape of Distant Worlds), close the game and go to Main Disk >>> C: >> Feralheart > exports and see if the map you exported the name is there.
Example. Let's say you named the map as~ Storm Clouds and you see it in exports as Storm Clouds .FHM
Hope I made sence, if you need anything else connecting with maps PM me and I will get back to you A. S. A. P.
Good luck! ^.^