I subscribed to a mod on steam a while ago titled "ugh you got me" the author later removed the mod from the steam workshop and I haven't been able to unsubscribe from the mod I am not sure why it might be because I am on mac please help.
All mod version from A17 to 1.0 are still at the workshop.
Worst case scenario, you can find the folder that stores the game settings and delete the mod list - I think it's some XML file. You can also, if you use Steam and want to clean things up, delete the entire Steam workshop folder, and it will force a re-download.