The Works in Progress section is for when you have content for your Mod that you do have created, but the mod itself is not ready for public release.
As it is now, you have an idea for a Mod you want to create, but you do not have content for it to work on or show yet. Annocing your intention to create a Mod is better done on a Profile Post as it is not suited for being a Thread on its own.
This Thread will be locked. If you have content to add to your Mod at a later time, you may Report this Thread to say that you have content for your Mod and request it to be unlocked, or PM myself or any Moderator about content for your Mod that you have. As it is now, it is not ready to be a Thread.