I understand I need to prove non-EU residence when I leave Schipol (for Switzerland) to get my VAT refund stamp. I have both a NZ and UK passport, so I assume that if I simply present the NZ passport and proof of address in NZ then this should be sufficient?
Presenting your non-EU passport won't be sufficient on it's own. You would also need to show that you've entered the Schengen area as a tourist, which would require you to demonstrate a 90-day entry stamp. If you did indeed enter the Schengen area on your NZ passport this should be sufficient.