i had the same problem initially, what i was doing wrong was this. never save the maps anywhere other than the folder where the program is unzipped, and never rename them, only select export and overwrite the .map file in the mods>*map_name*>.map file where the program was extracted/unzipped. then copy the *map_name* folder in its entirety and paste it into the civ 7 files.Hi,
Do you have the issue only with the maps you created or also with the ones you download?
For example if you download this one and copy to your mods folder does it work for you and is visible in the game menus?