Yesterday I suggested you solve your "boxing in" problem by using plastic trunking like the CH engineer did at a house that we intend to let out. I expected lots of guffaws or flames from people but surprisingly it didn't happen - maybe this time eh? :o)
We hung lining paper on the walls (except for the living room where we used an anaglypta / blown vynil thingy type paper) then he placed the trunking in position and then I emulsioned over everything - and I must say that we're quite happy with it.
My photography isn't up to much but it'll give you an idea of how the trunking looks anyway.
HTH,
Mogweed.