Currently, World Managers can choose to restrict access to their worlds so only people who belong to certain Facebook Groups can visit it. Unfortunately, Facebook has decided to stop allowing external programs to get the list of groups that a user belongs to. Therefore, we are forced to remove this feature from Kitely. This will happen on March 27, 2015.
If you are currently using Facebook Groups for access control then you should switch to a different method of restricting access to your world: e.g., using OpenSim groups. Otherwise, once we’ve updated the system your world may become accessible to more people than you had intended.