A few things...

First, I don't see any eligible way to use TN on PPT-TYO. Are you seeing a Qantas code on the PPT-TYO flight anywhere? Otherwise, it appears that you'd have enough miles in the bank to fly back to Auckland and Sydney to get to Tokyo, e.g. ...DPS-SYD-AKL-PPT-AKL-SYD-TYO.

Second, although the trip isn't planned to take place until 2025, if it was booked today, starting from the UK (MAN or LHR) the base price for a DGLOB34 would be £6200 (plus a lot in taxes and fees.) If you started in Norway, the same ticket would carry a base price of £4433. You can fly one way from MAN to OSL in economy most days for under a hundred quid.

Now far be it from us to hijack your plans, but Tahiti is really the trouble spot in your desire to use Oneworld products to their greatest efficiency. Now maybe PPT is non-negotiable, but if it WAS an optional destination, you could use a Oneworld Explorer, with no mileage limitations, which would (or could, depending on your desires) provide a chance for additional travel, without bringing the Global Explorer's mileage limits into account.

For example, you could swap Fiji for Tahiti. Qantas fly nonstop from SYD to NAN. Or, if you're looking for a tropical or subtropical island break, have a look at Lord Howe Island, accessed nonstop from Sydney. Want a French-speaking Pacific island with beautiful beaches and landscape? Qantas fly from SYD to Noumea (NOU) on New Caledonia, from which one could travel to several out islands like the Isle of Pines.

If you DID switch to a Oneworld Explorer, you might be able to leverage more travel, over a longer period, than with the Global Explorer. Take for example this DONE4 route originating in Oslo: OSL-DOH-DPS-KUL-SYD-NAN-SYD-NOU-SYD-HND-SEA-ANC-ORD-LHR-AMM-DOH-OSL . This is imaginary of course and is only an example of an infinity of options available. This trip would give you lots of tropical beaches (or whatever) - Bali, Fiji and Noumea - and, if you wanted, a break from the tropics with a visit to Alaska on the way back to Europe. (Or it could be more tropical stops in Mexico, Central America or the Caribbean.)

But note that by not returning to the country of origin (Norway in this case) you'd still be able to use some of the Europe/Middle East segments allowed in the Oneworld Explorer. (You're allowed four flights and two stopovers in the continent of origin.) So in this case you'd land in London, but it would be a stopover, not a terminus. Months later (before the year's validity of the ticket expires) you could fly to, say, Jordan (could be Israel, Egypt, Morocco, Dubai, Greece, wherever) for a second (or is it third?) holiday, before ending back in Oslo, another hundred quid from home. Using the Global Explorer, you'd be well into injury time on the mileage front, but not with the OWE.

Anyway, some food for thought over the coming months. Now, to your questions.

1. You could include intra-Australia flights with the Global Explorer, but you'd have to count the mileage and segments. Remember open-jaw or surface segments still use one of the 16 maximum segments; even airport changes, like Narita to Haneda, or Heathrow to Gatwick, consume a segment, and you'd have to count the miles you would have flown between open-jaw airports, e.g. the train from DRW to ADL would consume a segment and you'd have to count the 1623 miles you would have flown.

2. Yes, full TPs and Avios.

3. Not necessarily. You can change dates easily; most people will book "dummy" dates when the flights first open for booking (around 330-365 days preflight, depending on the airline) then change to the "real" dates later. That's to lock in the price in case one is concerned that the price might go up if you wait. Date changes are supposedly free, but most OW airlines charge "service" fees (ha ha.) Changing the itinerary - connection to stopover, changed cities, etc.- requires the ticket to be reissued, with a flat fee (USD125 usually) plus whatever nuisance fees the airline adds.

4. Play with distances using the Great Circle Mapper (like the example above.) Remember to include the mileage between surface segment points.

5. You can see base fares using Expert Flyer. Additional taxes and fees are route-dependent, but you ought to browse this thread - https://www.flyertalk.com/forum/onew...periences.html - to see what people are experiencing. The choices of country of origin, the ticket's issuing airline, airlines used in the course of the trip, and stopover points can make a HUGE difference in the bottom line - 20% - 30% or more.

6. People are different. Westbound in the northern hemisphere (maybe southern too? Not sure.) generally is against the prevailing winds, so the flights are longer and the nights last forever. You're passing through 24 time zones; so jetlag is going to be an issue from time to time, with no escape. That's one reason that flat beds in business class are beneficial.

Happy planning!