There is IK in Studio 3.1 and 4, but I'm pretty sure it's not compatible with Poser's, as when I load V4 in Studio 4 there is no option to turn it on.  For each part; there is an option to turn IK on when I right click on a body part, but it doesn't seem to do anything unless I pin a joint.  However,  I could have overlooked something, (I'd read the manual, except there isn't one) so as Laurie says, you mught want to ask in the Studio Forum....

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