I have tried offsetting a line, copying, exporting as a DWG/DXF and re-importing, exporting to C3D (forgive me!) as an XML and saving as a DWG... Some of these methods sort of work but the results are poor. If I check the linestring using the object explorer the elevations at the same point on the alignment and linestring do not match.
The other very noticeable thing is that the curves from the original alignment when exported as a DXF or DWG and then re-imported do not match by approximately 2cm (in my test case). The DXF/DWG is chording the curves. Is there a place to adjust this value?
Any help gratefully appreciated.