A shameless plug for a thingiverse thang I posted last night...
If you're looking for an OpenSCAD model of a zero (maybe to check a case design or a robot model) then try here:
http://www.thingiverse.com/thing:1638529
At present I've only played with the v1.2. 1.3 will follow soon. Yes, I know the main difference is the CSI, but I'm also modelling the PP test pads on the underside and they've been subject to many changes.