To show Diodes/Resistors in VeSys Harness you can use either a splice table or connector table, the part number for the Diode/Resistor can be the Main Part number of the component. In some case the ends of the Diode/Resistor may be 50mm or 2 inches apart which has an impact on the wire length, to work around this you could do any of the following:
Place 2 seperate splices 50mm/2 inches apart only assigning the Diode/Resistor part number to one of the splices.
Setup the Diode/Resistor in the database to have an 'Add-on' value of -25mm/-1 inch for both cavities and place one Connector/Splice in the drawing.
Place manual length adjustment on one or both of the wires.