Even if you don't have a NZ Licence, NZ authorities will create a dummy one, which any demerits will be recorded against. (note only offences where you are stopped and given an infringement notice incur demerits, speed camera and other stationary violations do not).
You need to be served with a suspension letter before a suspension can take effect, but there is currently a legal challenge underway which may mean that the processes that are followed, pre suspension are legally invalid, as are the suspensions. af