Hi,
I understand that you have to get Australian registration before you can apply for a 457. This will "prove your trade".
To get registration in Australia you need to apply for it at the Australian Physiotherapy Council.
http://www.physiocouncil.com.au/
http://www.physiocouncil.com.au/fold...10.2494730009/
You will not only need NZ registration, but also a NZ APC (annual practicing certificate) for the application.
Hope, you didn't sign the NZ application form where it says that you intend to practice in NZ..... just a thought....
Good luck,
Fyzzio