can someone explain the GUI.Window states for skins?

can someone explain the GUI.Window states for skins?
I’m trying to get my window to only change its sprite when I click on it or when I have clicked on it and am still holding down.

However it seems that it doesn’t like to update to the normal state after I release my mouse button

ok so I think this is a bug.
I got the button skin working but it seems the window skin behaves differently?

can someone care to explain this?