You can rename or remove existing schematics by right clicking on the schematic
name in the navigation window.
A circuit file can have any number of schematics. A list of all the schematics will
appear in the navigation window. The selected schematic is shown in the frame to
the right of the navigation window. You can change the active schematic by double
clicking on the corresponing schematic name in the navigation window. This will
update the frame on the right.
Any schematic can use the results of any other schematic, as long as you do not
create a circular reference between the different schematic items. To see how to
do this, refer to the block schematic component.