They'd get: The host has selected a map that doesn't exist on your installation. Attempting to download it from the CNCnet database.
Downloading custom map failed. Requesting the game host to download it to the CNCnet map databse.
The host has failed to upload the map. The host has to select a map published with the game or you will be unable to participate in this match.
Me and my family as well as other random online players have been playing my custom map (Which is also INI modded) and they would be able to receive the map fine. But now, all of a sudden, all players are unable to download it. How come?