Never mind on the model. I was able to repeat the bug here. What happened was I rewrote (ported) the OBJ export plugin recently to use our newest SDK features (RhinoCommon/Eto). One of the things I missed was setting the default number precision to something reasonable. It was set to 1. So any floating point number was turned into scientific notation. I haven't determined if Rhino is handling it wrong on import or the lack of precision in the output makes the round tripped file a piece of junk. ZBrush may have issues with scientific notation too if it's telling you no vertex was found.
I'm not even sure if scientific notation is allowed in OBJ for that matter. I'll have to look at my string formatting line and see if I can come up with something better/different.
In the meantime, you'll need to set the significant digits in the formatting tab to something appropriate, if unsure just use 17. It will keep that setting after you set it once.
To any other users running the WIP. If you've gotten one of the WIPs over the last few weeks AND you've actually run OBJ export, you'll need to check the significant digits. If you haven't run OBJ export in the past couple of weeks this will remedy itself in the next WIP.
Sorry for the inconvenience.