After your helpful replies I have now come up with the following:
HKG-oBKK-xSIN-xMEL-xSYD-oCBR-oSYD-xLAX-oLAS-xLAX-xSFO-xHND-HKG
That gives me the correct 4 stopovers so no additional payments.
The total distance is 21663. I was wondering if anyone can spot another milage/TP opportunity that I can squeeze in to use up those last few hundred miles. I know I am being greedy but flying is part of the holiday I really enjoy so I am happy to take loads of aircraft to get to my destination!
Anyway thanks so for for your help - at least I now know how to write the proper lingo for stopovers and transits
Regards
aks120