Map editor Saving with Any Clan as first faction borks any future edits.
Saving a map where the first player faction is set to 'any faction' causes it to become invisible in the loading menu, essentially locking the editor out of making any future edits. One can play the map, but never edit it again. All the other factions can be set to any faction; just not the first faction. Saving the map you're making seems to be tied to the 'identity' of the first player faction. Which, apparently, cannot be 'any'.