Developer reply by flod
Rated 3 out of 5 stars
This add-on is incompatible with Thunderbird 4 to 6.
This review is for a previous version of the add-on (3.3.1).This add-on is compatible from Thunderbird 2.0a1 to 9.0a1. Please check your firewall, something is preventing Thunderbird from checking the compatibility with AMO (this overrides compatibility values expressed in install.rdf).
To create your own collections, you must have a Mozilla Add-ons account.