Yep - I got the green certificate. Before I did the kitchen I spoke to the compliance guy (actually booked it in for compliance) , and he talked me through what I needed to do. I did it through SCNZ here in Auckland.
The grey water tank needed to be vented to the outside, and the vent pipe had to go higher than the sink drain, so I ran it from the tank up into a U bend and then back down and through an existing bung hole under the drivers seat. see photo.
View attachment 311763
The toilet cassette just needed the vent to be blocked off, which he showed me how to do it.
When I went back for "recheck" It flew through.