Inverse Kinematics sets how body parts move in relation to each other. Setting them on for the legs make the feet stay still when you move the hip. Just under that, in the figure menu, is Use Limits. This limits the movement of the body parts to what Poser has determined to be "realistic". Poser's view on realistic can sometimes be more limited than what you want. The Miahi hair just doesn't work well with the Firefly engine. I think there was a fix mentioned in the forums somewhere. Do a search of the Poser Forum for "Mihai" and you should find it.