When creating a custom map in Age of Mythology: Retold using the editor, it is not possible to start the game unless all Human Player slots are filled with real players.
This makes it impossible to create certain custom game modes, which can be played solo or cooperatively with different numbers of players (1, 2, 3 or 4).
This bug severely limits the creation and playability of custom maps, reducing the creative freedom of the modding community.
Important note:
This issue occurs with scenario maps. Random Maps are not affected and work as expected.
Suggestion:
Allow maps to start even if some human spaces are empty, or force the game to start as the host of the match, just like in the editor’s test map.
If necessary, treat unfilled spaces as “disabled” instead of blocking the game from starting.
As @TeacherTony mentioned in your bug report, there is a mod called “Allow dummy AI players” that can fix this issue.
I’m mentioning it again here, in case it helps other people while we wait for the developers to officially fix this issue.
Otherwise, the other solution is to generate the same scenario several times for X number of players. It’s a nightmare to manage, especially when we make updates…