Split from FS#465 by Stefan:

After more testing, it seems that a solid triangle causes trouble, perhaps correlated to Z-coordinates and the property editor.

Attached you find a dxf example file with only 7 objects. Three noticable cases:
- Selecting all and change Selection in the property editor to "Solid" flips to "No Selection" although objects selected.
- Selecting all and change Selection in the property editor to "Line" shows "Length" and "Angle" in Geometry with "*VARIES*" values although only one line is selected.
- Selecting all but the solid object (6 objects selected now), everything works as expected, in particular Selection "Line" shows valid values (and Z-coordinate 0).

I hope this helps, please give instructions how to help if necessary.