Quote - ...In Poser 9, as suggested, the hair doesn't take up the right scale at all and she ends up with a bald spot. :(I think it may be safer to use V4 for this project.

That's not an issue of scale, but one of joint parameters and mismatched rotations and object centers. In P2012, you can click options for conforming items to align such things appropriately, but that doesn't always mean they will work perfectly. You have to go in and edit the joint parameters for that hair object in order to get them to yield good results when fitting to certain figures, especially where scaling and joint rotation centers are moved.(...forget what they call it, somewhat like morphforms and how DAZ's Genesis joints can be repositioned on the fly.. whatever.)

Anyway, edit the joints and the centers and it will work fine. But, you'll have to do it for all the joints, not just the ones that have geometry associated directly with them.