If you're referring to the mod portal, it hasn't really had good support since almost when it came out. It's often down, and for a long time now has been running on http protocol even though all the old links say https. Best advice I can give you is post your mods on the forum, in the completed mods section. I put even my alpha mods in there, as long as they're at a playable state. The forum offers a decent system for posting images, attaching files, and alerting your fans when you post an update. It's not perfect but it's way better than the mod portal that we have.
Furthermore, don't rely on the mod portal or the forum to maintain copies of your mod. You should keep backups on a secure computer, or in Google Docs or Dropbox, or attached to your email.
https://openxcom.org/2018/01/dont-use-the-mod-portal/