First question. What are you currently flying on in the U.S.?
Is that type in use in NZ and is there a sim there?
If so, do your atpl flight test in that type.
I wouldn't go the CPL route, you already have an ATP and if you go the CPL route you need to do all the ÁTPL exams in NZ - a lot of extra work and expense for no benefit in my opinion.
Get your logbook assessed by ASL to start with and then go from there.