Does anyone have experience of simulating lumped element within geometry in FEKO?

I want to add a lumped capacitor between two metallic strip in FEKO (in construction that capacitor will be etched to metallic plate), if I want to use non-radiating network as lumped capacitor, which kind of port, should I use so that it can be connected to that network? I use edge port but it has no effect because lump element sees infinite impedance from that port.

another port doesn't appear in schematic view and others couldn't be used.

thanks.