In typical fashion Linux is not mentioned on the Nikon Firmware update page. And they do not give a link to download the .bin file that is neccessary to update the camera. The .bin files is however just embedded compressed in the .exe file. So it is pretty easy to make extract it for linux. Here is a step by step guide:
- Make sure you have unrar installed.
- Download the .exe firmware file for windows from Nikon sites.
- Extract the .bin from .exe file: unrar x F-Z6-V330W.exe
- Copy the .bin to the memory cards root folder. (Need card reader, can not be done with the USB cable connected to the camera).
- Settings menu -> firmware version -> upgrade.