Click on any reference or instantiation to highlight it.  To add a new reference, select “New reference” from the “Build” menu.  To add new instantiations to an existing reference, highlight the reference or one of its instantiations and select “New instantiation”.  To edit a highlighted reference or instantiation, select “Edit reference” or “Edit instantiation” (depending on what you’ve highlighted).  To delete a highlighted reference or instantiation, select “Delete reference” or “Delete instantiation”.  Note that deleting a reference deletes all of its instantiations.

Changes are saved to the module file as soon as they are made.  This allows you to insert and resolve references in the current document as you build a module.