Unfortunately these just ended up taking up too much time, and not quite enough interest to keep going with it. That and I sold my Z and got a car with a built in navi and music system (I know).
I am glad to hear someone else is working on something similar. Hope it works out for you guys.
If anyone has the product from zPilott that could help out in creating another one then please PM me or post here. I've tried to get in touch with zPilott and also MattJackson86 but neither have responded since they last where on the forum a couple years ago. I am looking for the source code for the V1 program as well as schematics to be able to build my own since they are no longer being made (and i don't want the bluetooth version)
A bit of a tangent, I went with RadarActive on an iOS device. You buy a $99 piece of hardware from them that plugs into your iPod or iPhone and the other end into your V1 and provides a remote display over a google-like map, showing your current location and other poi's. Pretty rad. Even if you have to buy a separate iPod for it, makes one badass remote display!