It seems there hasn't been any new recent uploads to the game's workshop in a very long time. There also has been recurring problems of not being able to upload to the workshop as well.

Feel free to join the nexus community and let's share our mods there!

Here is mine:
https://www.nexusmods.com/lowmagicage/mods/4

You can examine my file structure to learn how to set yours up in a clean way for separating yours from the base game and other mods, to the best of my ability that I've found. Using folders (You can have multiple images in your folder for packs.) and names.