Nav
 

I am in New Zealand and bought a Japanese imported 2012 Volvo S60. The Sensus nav gear is in Japanese and I wonder if there is an easy way to uninstall the software and install NZ maps

I used to do this work in NZ on BMWs. Successfully too.

There is a lot of software dependencies.
You can only try... it may or may not work... the first attempt is a real leap of faith, at a cost.

The nav and audio system sit on their own MOST fiber ring, and are coded to the car.
You may have issues
You will likely need to disable the MOST bus security, which checks serial numbers on the audio system against the CEM.
You will have to buy the upgrade to disable the security from a dealer
Then you can try exchanging the jap nav for a Euro nav.
You may need to exchange wiring looms as well.

It may proove to be such an effort that you might find it easier to sell the car as-is and buy one with nav fitted.