GuiCheckBoxCtrl
 

Once again, I'm not sure if it's intended to be like this, but..

If you set 'active' to 'false,' it looks like it's unchecked regardless of whether it is or isn't checked.

The checkbox gfx has no inactive image so its using the unchecked highlighted one, may be we can add one sometime

Couldn't you just use the image for when you click it? :)