Thanks for that - converting to R12 or R10 DXF seems to do the job.

Very promising plugin, but it's not 100% for my application. I'm looking for something to allow me to import planar DXF exports of lasercut plans for 3D printer parts (for extrusion and export as STLs). The built-in DXF importer in SketchUp 2014 worked fine, but that Pro-only feature has now expired in my free version. I tried installing the 0.8.2 revision, and everything came in more or less OK, except some of the curve fits to SPLINE elements are pretty chunky. Is there any way to improve the resolution of those curve fits? (I've got no control over the DXF itself - it's what I'm being given by the printer maker.)