Hmm. Trying to select the actor fails with:

Traceback (most recent call last):

  File "C:\Program Files\Poser Software\Poser 13\Runtime\Python\poserScripts\My Light Scripts\LayoutColumns.py", line 5, in <module>

    actor = poser.Scene().SelectActor("pillar3")

poser.error: Error parsing SetCurrentActor()

Usage: <NoneType> SetCurrentActor(<ActorType> actor)

Could it be that I've built my prop badly? It consists of multiple pipe sections and a couple of toruses.