Just use this websites surl "http://dl.openfastdl.net/tf" ?
It says just post a mediafile/other direct download on here in suggestions to get reviewed by the owner of this website/their software, then the maps get added to "http://dl.openfastdl.net/tf"
then type these in the console when server starts to allow people to download the map from the url
sv_downloadurl "http://dl.openfastdl.net/tf"
sv_allowdownload 1
sv_allowupload 1
Hope that helps guy 🙂