Originally Posted by sbiddle

If you had asked the question in the way you did here it's not surprising you didn't get a response. 99% would probably not understand what you wanted.

If you call Air NZ (or SQ and BA) and simply ask for the SQ and BA PNR's associated with your booking and give them your NZ PNR and your details you'll get their PNR which will allow you to change seats, check in etc from the SQ and BA websites.

There is nothing difficult about what you want to do and it's something I do all the time normally just by ringing the airline involved directly as there are occasions where Air NZ don't necessarily have the mapped PNR of the other airline if it's not a codeshare. My pick would be you simply totally confused the Air NZ staff, especially if you started asking about Galileo.