I just finished reading this:
and it made me recall the challenges we recently went through (although we were successful). In retrospect, especially coming from the US where there is a much lower regulatory environment, I advise everyone pursuing this route to get an immigration advisor who is experienced with the business visa residency, employment law, has access to or can recommend an accountant familiar with immigration NZ, and lastly seriously consider whether you want to gamble with your time and investment dollars!

If ANY aspect of your operation does not meet immigrations requirements you will not gain residency. You must make the investement and the investment dollars need to be traceable from the moment they were earned to your non-NZ bank account, need to be transferred to NZ correctly with proper documentation, you need to exceed your business plan projected profits in the time you set out to, you need to hire the minimum number of employees and need to hire them correctly with employment agreements that meet INZ's standards, and you need to do this all in the timeframe allotted. There is a reason that the vast majority of business visa holders don't gain residency having to leave the country!

Beware and tread carefully!