Notice this, in case it affects you.

Note: If, under the provisions of a Double Tax Agreement (DTA), you also have tax residence status in another country, you will not be considered to have tax residence status in New Zealand for the purpose of meeting the requirements for a permanent resident visa.

New Zealand has DTAs with Australia, Austria, Belgium, Canada, Chile, China, Czech Republic, Denmark, Fiji, Finland, France, Germany, India, Indonesia, Ireland, Italy, Japan, Korea, Malaysia, Mexico, Netherlands, Norway, Philippines, Poland, Russian Federation, Singapore, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, United Arab Emirates, United Kingdom, and the United States of America.
http://www.immigration.govt.nz/migra...quirements.htm

There is more information about applying, here. http://www.immigration.govt.nz/migra...teps/apply.htm