Rated 4 out of 5 stars

Could be improved by adding ability to backup and restore GreaseMonkey scripts

This review is for a previous version of the add-on (3.3.1). 

FEBE?

Did you mean FEBE? CLEO is an extension/theme packager, not a backup utility. FEBE can backup/restore greasemonkey scripts using "User-defined" backups.

See https://addons.mozilla.org/en-US/firefox/addon/2109