How to play a custom scenario?

So I recently bought the game, and i've been trying to figure out how to play a custom scenario. Suposedly it appears on the custom map choice when creating a game after downloading it from mods, but this one in particular (at least for me) doesnt. It's "City of Peace". If anyone can try and tell me if it works or where I am mistaken, please do; thank you.

(Other maps like "Hotkey trainer building" do appear to me the regular way)