I came here on a research trip last year during which I visited a few schools and from my talks with principals I learned it was important to have the full assessment before applying for registration as the registration itself is a condition to work as a teacher in New Zealand.
I double checked with
http://www.teachnz.govt.nz/overseas-...ps-to-complete where you can find the 4 steps to follow with full assessment and obtaining registration as the first 2 steps.
When I submitted EOI my application with NZTC was still pending so I couldn't confirm (it is a separate question on the online EOI) that I was registered as a teacher and therefore I wasn't considered a skilled migrant hence EOI not succesful. (Not accepting my degree was simply a misunderstanding and easy to rectify.) Only after receiving my registration and practising certificate they considered me Secondary teacher and issued ITA.
I have 4 months to complete it but due to the fact that most of my paperwork was already requested by NZQA and NZTC it is merely a formality which won't take too long hopefully.
I really don't know what happened in your specific case as the registration is an important element in the SMC-route but I can imagine this must be very hard for you and like I said, I really hope this works out for you well!