In praxis IK is a way of keeping the hands or feet "nailed" in place whilst other body parts are moved, or of translating a hand (or foot) and having the arm follow the motion, rater than the hand pulling away from the wrist. Whilst IK is on you can parent a hand or foot to some other item in the scene, this is handy when a sword or similar must be held in both hands, eg parent the sword to the chest then parent both hands to the sword, or parent the sword to one hand and parent the other hand to the sword. I think IK chains are also used by the Walk Designer. Most characters load with leg IK on by default, I find this a PITA, so I set up my most used characters to load with leg IK off. here is one way: Back up the cr2. Load the cr2 in a text editor, use the Search function to find "inkyChain" the name in this line will be something like "rightLeg", add an underscore "inkyChain right_Leg" do the same for the other leg, save the file back to disk. Load the character in poser, turn off IK, save it to the same pallet as "Z". In a file management utility (eg Windows Explorer) find the original cr2, copy its name to the clipboard, then delete the cr2 (you did back it up, yes?), select "Z.cr2" and rename it using the name stored in the clipboard. This last step was so as to preserve the original thumbnail, if you had resaved it in the previous step using the original name the thumbnail would have been overwritten.