Consider this a basic rule:
- If you have a functional download available, it's a Working Mod. If it works but needs testing still, please consider tagging it with Alpha/Beta/WIP status, or a version number. Not required, but it helps others to track progress. Bottom line, if people can actually use it (and it doesn't crash the game on startup), then it can be considered Working. That's not to say you have to post it in WM, just that it must be functional to be posted there.
- If you have nothing to download, if the mod is nonfunctional, or still in WIP/theoretical stages, then post in Mod Development. If you're still working out the design, if you have no screenshots and no downloads available, then it does not belong in Working Mods.