I was able to fix the sizing bug, and I also was able to add the ability to remove an individual button from the bar. So say you wanted to remove the SpellBookMicroButton, and not have a gap left, you can. And when you restore the SpellBookMicroButton, it will return to it's original position. I'll post the code here, or elsewhere in short while.

Pretty sure I got most of the kinks out. Current version is here: http://pastehtml.com/view/baianwgei.txt

Also modified how the HEIGHT_OFFSET works. It will now base the offset off of the button's HitRectInsets.

Code is posted here ==>> http://pastehtml.com/view/bai3rxey2.txt
I still need to do a little work to make the size slider and this new feature play nice together.

I've implemented your changes with a slight modification to pull in friendly names, if possible.

Awesome. :-)