Yeah, I dug out the copy of Jurassic Park I had nearby and read the parts regarding the Maintenance Shed and realized how similar the design of the shed was to that of the movie, I then combined those ideas with the partial mesh I had already made...
http://imageshack.us/a/img839/9573/msrender01.jpg
This is a rather large image so you can see the details a bit better. The implemented design is that the two big yellow pipes (the one on the right is the "dead end" one, the other one you see when Arnold's arm falls on Ellie) are the fuel delivery lines for the two tanks on the lower level, barely visible in this shot. The light blue box is the main generator. Electricity is generated there and is fed through a series of cables which then go up to the upper level at the "dead end" and go straight to the big room where it meets the transformer (green box). The output of the transformer is then sent through the circuit breaker box (dark blue) and then goes up the stairs where it exits the roof of the structure as a set of elevated electrical cables.
In the book, Grant enters the shed and heads to the left, then right, then down a ladder that's on the left... On the set there's a ladder that is to the left immediately after the elevated walkway... which tells me it might have been intended to be the same ladder and that the elevated walkway was over the "pit" the book talks about. At the bottom of the ladder there's two yellow tanks which say "Inflammable" and some Spanish beneath it. A white pipe connects these two tanks to the generator, which Grant follows to find it.
Here's some more interesting renders with some lighting added.
Here's the main walkway that you see in most of the Maintenance Shed shots. What's funny is that when Malcolm is telling her to follow the piping, she is at the end the breakers are on facing the direction of the stairs and ladder, and then after the cut she is at the opposite end of the walkway facing the other direction. Also note that there are three skylights in the ceiling near some of the light fixtures.
This area is the same area that is used for the Emergency Bunker shots, which should make it somewhat familiar to you guys. In the Emergency Bunker version of the set, the stairs up would be on the right side of the shot, next to that brace for the beam.
And here's a shot of the two fuel tanks and their bilingual warnings. I copied the warning from one of those Flammable storage boxes so if the translations wrong, it's not me
You can see part of a staircase there, I believe that was to be the one Arnold uses in the book before he realizes the raptor can jump down the 20 feet distance. It's much steeper than the other stairs on the set. The area where the camera is would be the underground garage where Gennaro's truck is... this would link into the underground tunnel network we see in JP: The Game I would think... The door will just be a shuttered entrance though when I make it.
Obviously there's still a lot of work to do to get it finished, mainly with the piping and machinery.