I suggest you try again to see the video - it's not a masterpiece (lol?) but it does give you some idea of what I have built.
I am not sure if the questions around sealant have anything to do with the water loss. I used a sealant to stop - or at least reduce - the water going down the back, instead of the front of each 'face' (is that the word?). As far as I understand it, this was a 'horizontal' application of the sealant.
Because of the weather, I have not had it running all the time, and I probably will only be able to check this out in the spring.