In my attempts at creating my own characters and delving into the depths of the Setup Room I encountered a problem I just can't find a solution for.

Namely, when scaling the head of the figure it scales different parts of the head differently, scales one half of the neck but not the other etc.
I just have no idea what causes this and how to remedy it. Every bit of help is appreciated here.
The first example is the head scaled in Poser 5.0, the second one in DAZ|Studio.