Ok that about what I have were I live in Sweden.
The way I and many others keep our bees in poly hives is with no ventilation in the top and ventilate with a metal screen over 70% of the bottom and an open entrance that wont allow mice to crawl in.
I myself and many other have a Swedish raised bottom board called universalbotten
http://www.pixonia.com/universalbotten2011.pdf It has a metal ventilation grid in the rear that works like the back wall of your fridge and attracts moisture.
The front entrance is also open so air can flow freely across the bottom so the moisture ventilates out.
In the winter time with freezing temperatures the air is often very dry and helps keep hives dry.
None of my hives have the amount of condensation I have seen in your pictures and never over the hibernating bees, eventually a little moisture or frost on the outer skirts of the ball of bees.
All though I haven't looked at them on a continual basis under the whole winter. Just now and then in extreme causes.
In a nut shell our hives have a warm winter cap and a drafty floor to get rid of moisture, the walls may bee wet with condensation that run down and out of the hive.
This is just info on how most of us do it here :)
Hope you learn a lot with your experiments and they work out, if not you have some more ideas to play with next winter ;)
mvh edward :-P
PS if the link doesn't work you can google " universalbotten " and look at the pdf file or google pictures and you can see the different bottom types.