I finally tried to play around with the Face Room in Poser 5 and have decided that it's too much trouble to do anything worthwhile with. One of the most annoying problems is that the real-time head is stuck with a fish-eye focal length that distorts the face as if it's projected on a sphere. Getting the head to look good in the Face Room results in something that doesn't look the same once the Face Room is exited. I suppose, with practice, I could learn how to get around those differences, but don't consider it to be worth the trouble.

One thing that might help is, once you get your head done, spawn it as a morph target (there is an action button that will do that instead of applying it to the head). You'll find the head and eye morphs in the "Morph" section of the Parameters window (once you get back in the Pose room). Then you can dial in the amount of change you want to apply to the actual Poser character. I find that you actually get better results that way. I'm also working on some morphs that will allow you to add more shape to the heads outside of the face room. It's in beta testing right now.