Issue 201 of Retro Gamer magazine has a ten-page article, "Jet Set Willy: A Guided Tour", which includes a map of the mansion, and room-by-room comments by its author, Matthew Smith.
For each of the 60 reachable rooms, there is a screenshot, and a few lines of Matthew's comments (sometimes in the form of questions and answers).
Matthew admits that he didn't have the time or energy to fill in the vast empty spaces in some of the rooms, because of pressure from his colleagues. For example, he was planning to do more with "East Wall Base", as the gap in the right wall implies.
But where he did put the effort in, he came up with masterpieces such as "The Nightmare Room", "The Banyan Tree", "Orangery", "Tool Shed", "The Wine Cellar", "The Forgotten Abbey", and the most iconic "To the Kitchens Main Stairway".
Matthew mentioned the four "lost rooms" in the context of "Tree Root", which has its unreachable right exit set to the empty room "[". "I seem to recall they were up on the roof somewhere, but maybe there was one off here... I think there was a chimney stack in one of them, and I was going to have another room on top of that."
I'm guessing that the chimney stack would have been above "Rescue Esmerelda" rather than "The Watch Tower".
Matthew identified some of the sprites, which have been the subject of much debate in the MM/JSW community. For example, the one in "The Bathroom" is "two Earths rolling after each other", the vertical guardians in "At the Foot of the MegaTree" are "a bear, wearing overalls, like Rupert", the bald guards in "Rescue Esmerelda" are future Ocean boss Dave Ward, and the heads with six legs in the Ballrooms are a "Bug-Byte bug".
Discussing the rumour that a raft would appear in "The Bow" at 11:45pm and take you to an island, he said, "I did think about having stuff happen at different times, like the graphics changing when it got to night, and the Off Licence closing."
I could go on and on, but I have now exceeded my quota of MM/JSW activity for the year, and it's not even Christmas yet...
Edited by andrewbroad, 20 December 2019 - 02:19 AM.