TTMRA
The TTMRA is a one off conversion. If you converted your CASA CPL to a NZCAA CPL you will be unable to convert a latter gained CASA ATPL to NZ. However you will be able to go back the other way ie gain a NZ ATPL and convert to CASA.
I have just had this very discussion with NZCAA and CASA in the past week. Hope this helps.