Normally Poser 6 (and above) puts two props in every character you load into a scene, "CenterOfMass", and "GoalCenterOfMass" (at least that's how it's supposed to work). The both of them occur in three places in the cr2 (like any other prop), the declaration section, the definition section, and the figure section. It does no harm to text edit the cr2 to delete all of them, but you should delete all trace of both of them, leaving stray parts behind, or deleting one prop without deleting the other, could cause problems. CR2Builder is a good tool for getting rid of them, but...

...As soon as you load the figure it will put the two props back in there again.

In P6, I have never come across more than one instance of the pair of props in a cr2 that only contained one figure. Perhaps it's a P7 only bug?

These props are a damned pain, it might have made sense to add them to the figure when and if the "Auto Balance" switch was activated (which in my case is never), but to put them in there by default, is the Poser equivalent of spam.