The information is taken from data already in FamilySearch so you do not need to enter any additional names.
Clicking in a segment shows you summary information about that individual:
Clicking on the circle icon in the upper right of the information panel shows a ring chart for this individual. The rectangle icon provides profile information for the same person:
Clicking on the pencil icon takes you to nFS and where you can edit the information. Once you return you click on the synchronize icon and the information on the ring chart is updated:
Notice the original profile showed that he died in St. Louis City, in Missouri Territory. Actually, it should have been St. Louis, St. Louis, Missouri.
Nice application, a quick easy way to see where your holes may be. Additional information is available for the LDS community.
Note: You must have an valid login for new.familysearch.org to utilize this site.