Originally Posted by Leumas
Hmm, so if I start in WLG, are you saying I can't do WLG-MEL-rest-of-the-world-SYD-WLG?
Sorry, I should have been even more specific. If starting in SWP, you can't cross the Tasman twice at the same end of the trip

. The rule, as I stated, is that you can only have one international departure and one international arrival from/to the country of origin (expect for the some specific cases in USA and London in conjunction with travel to South America and certain African nations).
So, yes, you can depart NZ for Australia at the beginning of the RTW journey. Then arrive back into NZ from Australia at the end of the RTW journey.
The other rules relating to continent of origin are that you have a max of two stopovers in that continent and max of four sectors. And you cannot purchase additional stopovers or sectors in the continent of origin.
Also, can someone explain an 'open' segment to me? It seems quite important, but I'm not sure what it means...
An open segment is one which exists on your ticket with an origin and destination, but no specified date, operator or flight number. This allows you to confirm later for the actual date, carrier and flight number you want to take.
The advantage of an open ticket is that you don't need to re-issue the ticket if you need to change a date/time, carrier or flight number. But you must use a carrier for which your ticket is valid - meaning a OneWorld carrier for a OneWorld Explorer ticket. And you cannot change the routing (sector origin and destination) without re-issuing.
The disadvantage is that you may find availability become tight at peak times closer to the travel date.
The ticket will show the open status of the flight segment in the "Staus" column, while a confirmed flight sector will show "OK" in the Status field.