In my experience any exchange of air between the strong colony below and the weak ones above will cause too much condensation in the colonies above and lead to their failure. I simple 1/4" luan sheet between them works fine as it allows heat through but no air. If you need a bottom entrance (I wouldn't want one) you can put the dividers on that if you like. I would give all of them a top entrance so I would cut the luan to fit the bottom hive and put shims under it to make the top entrance and, maybe put some strips of wood on the top to make a beespace under the frames of the top colonies. A 1/4" luan divider in the top box could make it into two nucs with the same heat sharing qualities.