It may be a problem with your setup, not with the theme files.

- Check up your internet connection.
- Delete your cookies.
- Refresh the add-on's page.
- Make sure your Firefox version is up to date (this theme may not suit earlier versions of the browser).
- Try again later.

If it works on a later attempt (and you happen to like it) please consider changing your rating.

Gracias, Pablo! Qué bueno que te guste.