I seem to be having a problem, perhaps a bug, with the size 2 cargo bays. The deployment slider only seems to be able to control the maximum closed size of the bay, not the maximum amount it opens. Example.
The first picture is of the bay 'closed', and the second is of it opened. I also tried editing it from both a fully closed and fully open state, but the second the slider moves, it reverts back to a 'closed' state and saves the new slider position as it's closed position. I'm not sure if I'm doing something wrong or if this is not how it's supposed to function.