Fnd_List_AddButton

            Fnd_List_AddButton (button label)

              Parameter                   Type             Description
              button label                Text             The new button’s label

            The Fnd_List_AddButton routine adds a third button to Foundation’s choice list or command dialog.
            Pass it the button label to display. If the button is clicked, the dialog will be closed and the OK variable will
            be set to 2.
              ALL RECORDS([Products])
              SELECTION TO ARRAY([Products]ID;$productIDs_ai;[Products]Name;Products_at)
              SORT ARRAY(Products_at;$productIDs_ai)

              Fnd_List_AddButton ("New Product")
              $element_i:=Fnd_List_ChoiceList ("Select a Product...";->Products_at)

              Case of
               : (OK=1)  ` A product was selected.
              		 ... ` Use $element_i to determine the selection.
               : (OK=2)  ` The "New" button was clicked.
              		...
              End case