First quick answer:
poser.Scene().ActorByInternalName("BODY") returns the first body actor found in the scene. This is not necessarily the one you wanted to find.

Either you specify the index number of the figure from which you want the actor (so for example "BODY:3"), or you use the corresponding function of the figure: poser.Scene().CurrentFigure().InternalName("BODY").

By the way, the "Scene" object remains constant. It does not change. So you can set SCENE=poser.Scene() and later just use SCENE instead of poser.Scene() (capitalization because it is something like a constant; but this is not mandatory but just good style).

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