The map clearly was missing major textures in game, so I looked in the log and found lots of warnings like this:
warning: Unable to load texture: z:\home\%USER%\.faforever\user\my games\gas powered games\supreme commander forged alliance\maps\azalea_gardens.v0004\env\decals\wm_azalea_gardens_nm.dds
I have this path on my system:
'.faforever/user/My Games/Gas Powered Games/Supreme Commander Forged Alliance/maps/azalea_gardens.v0004/env/decals/WM_Azalea_Gardens_nm.dds'
Notice anything? Yes, I have a case-sensitive file system, and for some reason all paths were converted to lower case. No surprise then that it couldn't find the texture.
Is this a map bug or a game bug? Most maps look fine.