Ah - yes. I can't see a way of doing what you want (start in NZ, two stopovers in Perth, one before and one after SEL), assuming you do actually want to go back to NZ to finish. Otherwise you could do: AKL-SYD-PER-HKG-SEL,HKG-NRT-DFW-LAX-ORD-LHR-HEL-NRT-PER,MEL-AKL and either buy a PER-MEL or simply throw away the MEL-AKL.