I needed to use this form to get an immediate working visa to cover me while I had a retest of my immigration medical blood test.
In the event the delay was only a few weeks but basically it is for NZIS to ensure that non-accredited employers have gone through the correct procedure for recruiting overseas workers. It asks for details on the job offered, salary details and qualifications required. Then employers are also required to provide details of genuine attempts to recruit suitable staff already in NZ - such as where the vacancy has been advertised and for how long and why any NZ applicants were not suitable.
In my experience NZIS treat this very reasonably and are just looking to ensure that the basics have been covered not trip anyone up or make it impossible.
Hope this helps