[Mac] [WotLK] Missing or Corrupted Data "Failed to open archive interface.MPQ"

After downloading the client, fixing the text file within contents with chmod, and trying to replace the launcher with some file found in the forums, same error happens. Moved the app to Applications, nothing.

After i try opening the main file, i get

- Missing or Corrupted Data "Failed to open archive interface.MPQ"

The launcher gives me "Must be in the same folder as the game".

Redownloading doesn't seem to help. There's a bunch of topics on the forums with this same issue, but no answers.

Any help?