lori54, I think there have been floor plans done, but I don't think it is possible to do a definitive one, because the locations of the study and the Tower don't stay the same. And, of course, even stranger problems arise further on in the show.
As for Vicky going out the back door, I was assuming that she did so because that was the shortest route to the cliff, but I like the idea that maybe she felt she was supposed to use the servants’ entrance. I'm not sure it's correct, but I like it anyway.