I think there may be another thread on this project but I couldn't find it so I'll just reply.
I believe the focus is purely zone focusing. I see no reason why someone wouldn't be able to attach an accessory rangefinder to it however which would probably work pretty well. The lens they designed to work with this camera (which you have to find on your own) has a pretty wide depth of field so I think zone focusing would be rather easy.
I personally donated $10 to this project a little while back. I don't need the camera as I have a modified Polaroid that works really well as a "portable" 4x5 camera but I admire the spirit behind it so I wanted to lend my support.