Master_Shake
Thanks for your response.
Over the years (ACAD 10 - ACAD2015) much of my AutoLISP programming had/has centered around using 3DSOLID objects. ACAD 2004, for example, didn't offer the 3D WORKSPACES available in ACAD2015. So I'm not sure what advantages, if any, exist by using these newer WorkSpaces when programming in AutoLISP.
Thanks,
mgf