Any CadLwPolyline with a coordinate of 0,0 ignores that point as valid coordinate. You can use the following example from another post to view the issue. This will render a triangle rather than a rectangle.
using (Cad…...CadEdgeBoundaryPath path = new CadEdgeBoundaryPath(); path.Objects = new...new List(); path.Objects.Add(new CadBoundaryPathLine() { FirstPoint...