OK, autoturret takes advantage of the lights that define subobjects. Not only does the light terminate the herarchy branch, but it represtens the firepoint, or the location where the beam/laser/etc will originate.
The normal of the turret is calculated by the program drawing a line from the light to the center of the turret's geometry.
So, with all that aside, the turret should be named turret01(optional extra naming stuff here) and the turret's firepoint light should be named turret01-fp(more optional naming stuff).
Kazan will probably come along and correct me on things or explain in more detail something or another; he wrote PCS with the autoturret feature so I think he knows best.

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