Custom Maps Not Appearing

I have a bit of a funky issue. I have been working on a custom map and I even got it published to mod.io and when I setup the map on my computer before publishing it worked fine but when I published the map did not appear in the map list. Same thing has happened with other map packs I have downloaded, some appear and others do not. Has anyone else experienced this or know how to fix it? They are just not showing up in the list of maps to play on.