The most recent changes to the Facebook API have broken the NodeXL importers for Fan Pages and Groups.
We will be repairing as best as possible these importers by updating to the new API and its restrictions. We expect a release next week that will restore any remaining functionality that the API provides.
Apologies for the interruption in service. We will restore this feature as best we can given the increasing restrictions imposed by Facebook. This is a trend displayed by most of the platforms to increasingly restrict access to their data.