I'm happy I could help you, Joe!
The non-human and no standard creatures are very tricky but we are finding all their secrets!
Remember: If you want to be able to animate the tail, you can do: First create a Box, (plain box) near the lowertorso bone. Link the spring root dummy to this box. The rest of the spring, normal in a chain as you did. Assign a bitmap material to this control box, so you can see it in iClone but also can make it invisible cranking down the strength slider on the opacity map. (must have a bitmap opacity assigned too). Now when the cat moves, the box transfers motion to the spring root and the tail swings. But if the cat is stopped, you then animate the control box and can wave the tail as a happy cat!
About the boob bones in G3... Wrong! They are part of the character bone chain. What happens is iClone does not have controls enabled for those. Too bad, they have never seen a boob hoola in action! Wanna do it? Do the same. In MAX, look for the breast bones.
Unlink the first of each. Add a control box (let's call it that way) for each breast, linked to the lowertorso, then link the breast bones to each control box.
Now, you can "animate" at will the Bs, while retaining the springy, fluffy features.
For those late night club video shows !!!!
You have some minor errors in the run cycle. Look in Internet for animal walk cycles, or shoot a cat. (not with a 358 gun, of course) If you rotoscope some motions with iClone Motion editor 2.5, or with MAX (better) then you can have a perfectly running cat. Just one cycle is enough!
And feel free to ask any time. You are a good friend and I am ready to help!
Also...
If you have a nice sexy secretary or female cousin, maybe she can give me the mouth kiss....
lOl!

Mike Aparicio-Reallusion Certified Innovative Content Developer