I was working in the main branch and let me try to create my branch and commit later.
Meanwhile I can send you patch if you are comfortable.
In other hand, I’m not sure if the approach of this link is working to create dashed lines.
SliceIntersectionDisplayPipeline is using vtkActor2D, vtkPolyDataMapper2D and vtkProperty2D. Really vtkActor2D does not support texture but vtkActor does. But if I try to use vtkActor, it doesn’t support vtkPolyDataMapper2D and vtkProperty2D so I can’t access SetLineWidth.
Csaba already submitted this issue before.