The Navigator panel displays a tree of the UML Diagrams that make up the current document, and the UML Objects that are contained on the diagram.
Double-clicking a UML Object causes that diagram and that object to be displayed on the UML Diagram panel.
The Navigator panel also provides a short-cut to entering links between UML Object outputs and inputs. On the Navigator panel, UML Objects can be expanded to display their <<Outputs>>. One of these Outputs can be dragged and dropped on the Object Properties Editor panel to a specific UML Object <<Input>>. This Output is then entered as the <<Link>> expression of the UML Object Input.