Except you can't post it directly in Releases,.
If you submit your mod in submissions first, the judges will check that your mod is playable and doesn't throw any errors on normal gameplay (among other stuff) before moving it to the proper section in releases. If something is wrong, the judges will let you know in the same submission thread.
If you're talking about a mod that you're not considering as "done", you should be a little more specific about it, though.