There are only 3 roads in New Zealand you are not allowed to drive with your Spaceships campervan. The following roads are the 3 restricted roads:
Skippers Canyon Road near Queenstown (South Island)
Ball Hutt Road near Mt Cook (South Island
90 Mile Beach in Northland (North Island)
Also, you must not - unless authorised by us - drive or take the campervan on any road, which is temporarily/permanently closed or restricted, or on beaches through streams, dams, rivers and floodwaters.
See for more info about this.
All other roads in New Zealand are okay to drive when hiring a Spaceships campervan, including unsealed roads and gravel roads.