Citizen Hand CAT Rig problems

[ForrestMarkX]

I'm having a odd issue using the Citizen hands rig I got from here [url]http://source.maxofs2d.net/gmod/3DS2011_CAT_c_arms_citizen.max[/url]

I can't link any type of constraint with it, for example I want to animate a shotgun but I want to the IK Target to move when the model moves, I'd simply link a constrait from the IK controller to the model but this is impossible as any attempt at doing it results in "Link Constraint Not Completed"

Here is a picture
[url]https://dl.dropboxusercontent.com/u/52828637/Problem%20%282%29.png[/url]