You don't get any points for English language ability, proved by your IELTS. Being able to use English is regarded as a basic requisite of living and working in NZ, so it is a gateway requirement - being able to show that you can use English allows you to apply for residence (and if you couldn't, you couldn't apply).
No, there is no body with which you need to register.
Either your qualifications must be on the INZ list of qualifications exempt from assessment
http://www.immigration.govt.nz/opsmanual/35171.htm, or they need to be assessed by NZQA
http://www.nzqa.govt.nz/qualificatio...ns-assessment/, before you put in your EOI. The EOI requires you to fill in those details. Incidentally, it's a waste of money getting PAR. PAR levels are stated only on the basis of what the title of the qualification is, whereas for IQA, there is an investigation of what subject-matter has been studied, to what depth. After this, the IQA states which (if any) NZ course the qualification submitted can be considered equivalent to, and its Level, and it's mandatory for the Invitation To Apply, the next phase of applying under SMC. Use the form at Appendix B here
http://www.immigration.govt.nz/NR/rd...ifications.pdf to ask NZQA to look specifically for equivalence to the qualifications you need for bonus points for your job, as seen here under List of Skilled Occupations (click on green bar).
http://skillshortages.immigration.go...per-programmer