Hello Kevin,
with regards to the Australian & New Zealand Data Feeders thread there was and maybe still is a problem with the Comstation to ANRB Server connection. It is possible, that this has (hopefully temporaryly) removed the ATC stations too.
There will never be ATC available in germany as it is by jail forbidden to listen or redistribute ATC conversation. I don't know if there is a similar law in NZ too. If yes it's highly possible that AirNav will deactivate all ATC stations in NZ to protect the persons who are running the comstations at their homes.
Ingo