In my experience zeroing the figure and Memorizing that zeroed state is a necessary step in making a conforming figure. Poser only turns on IK for a chain named rightLeg or leftLeg (any case in the lettering), what you actually rename these to makes no diffrence as long as they are not either of these names, you could call these IK chains 'Fred' and 'George', the underscore is just an easy way to rename them. Poser does not automaticly turn on IK for rightArm/leftArm, or any other name.