Hello, I had an idea.
Research a map in a board like the plugins and mods. You can have picture to see a bit of the map, if you're sure choose this map and not the other, you click on download, it will automatically be in world cathegory. If you want download it for you, click the link like for mods and plugins.
Thank you for the read, hope this feature will be added, sorry for the few errors of spelling because I'm french, take care of yourself !