linking "sliders" that work

So far I have had luck linking my armature and model, but the IKFK sliders, although they are in the linked file because I grouped them, do not work. I have tried ctrl-alt P to import the slider parts, but they relocate to the center of the object. What do I need to do in my original file to get them to link properly?
edit- I am using the method from the Mancandy FAQ, where the sliders are made from new objects. I tried to use a bone to move the slider object, but it moves the object, not its center, so the switch doesn’t take place.

Since I’ve never used the ManCandy thing, I’m not sure how it works,
but I do know for a fact, the more you practice with drivers and strengthen
your understanding, the easier it will be to spot what’s wrong. Or even
repair it so it works again. I have been watching the IK/FK swith thread
and have a good idea, but I don’t feel bold enough to jump in yet.