This version of Zipit has been deprecated and replaced by a new version available here.
https://github.com/mhancoc7/zipit-backup-utility
You should use the Zipit Backup Utility Installer to install Zipit.
https://raw.github.com/mhancoc7/zipit-backup-utility-installer/master/zipit-install.php
Detailed instructions for installing: http://www.rackspace.com/knowledge_center/article/zipit-backup-utility