Might also zip through the options in the Repair menu, just in case there are some lurking artifacts, non-manifold stuff, etc.
It doesn't sound like a units of measure thing though. In./mm. would leave stuff off by a factor of 25.4. 285/200 = 1.425 sounds closer to a square root of 2 (1.414) or 10/7 (1.429) ratio. Nothing comes to mind there.
Sorry I can't help with the CAD side, though. Most of my work has been done in OpenSCAD....