"Using the Extended family chart to identify real islands in your database is very difficult, especially if you have a large tree."
There is a genealogy program called GENViewer that can be used to find "Real Islands"
It is quite helpful in helping a user with other aspects of their FTM Genealogy Data Base. And is very easy to port your FTM Data Base to this program
Info about this program can be found at the following address:http://www.mudcreeksoftware.com/genviewer.htm