Thanks Piotr. I did refer to other objects but couldn't make sense of the code. Turns out I was misunderstanding the commands. I finally got it right - however very much by accident

... mainly using GDL Reference Guide PDF as the most useful reference.
ArchiCAD 10 - 25 | Windows 10
ARCHIcreate | Perth, Western Australia
archicad solutions | content creation | training | software implementation