I found that if you try to draw a parallel to a spline you get a crash, error message:
If you convert the spline to Lines and then back to a Polygon, all is well.
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
If in fact you shouldn't be able to draw a parallel to a spline perhaps a message like "can't draw parallels to splines" or similar would be good.
I only discovered this using my BeamCamber script, which draws cambers as splines (I had forgotten this!); Example below:
Normally BeamCamber saves the camber data as text, loads it into MacSurf and then I import it back again as a dxf file and the spline is a polycurve. But this time I simply wanted to draw a camber directly in RealCADD ...
Cheers -- George