The 0.1.4 version of RepoZilla for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This free Mac app is a product of Amir Torres.
From the developer:
RepoZilla is a free to use application that allows you to install hosted or packaged apps, through manifest online, outside Firefox Marketplace. Apps privileged or certificates can't be installed with this application. This program has an easy-to-use interface.