Originally posted by noodle:

Hello, you must own the game on Steam in order to download mods from the site.

Hey noodle, I also can't download mods because of the greyed out button. I purchased Rebirth and all the dlc's through steam. I've tried many things like logging out and even different solutions such as using a different browser and reinstalled the game and its dlc's. I would really appreciate it if you could help me out :(