There's a scene in the script where the engineering section appears in the background of an on-screen communication, so I decided to see what I could come up with design-wise. With apologies to Aridas Sofia
for once again diverging from his original design, here's my take on what the main engineering section might look like in cross-section:
There are several important things going on here:
I've located engineering further toward the aft end of the ship, closer to the main engines and the aft "toroidal loop interconnect." Early on I posited a large ring or loop within the saucer that intersects the connecting conduit between the drive spheres at two points. I had the vague idea that this loop is the main component of a toroidal fusion reactor for generating most of the ship's power, and that it is also connected directly to the FTL drive system. There would also be a power distribution manifold located dead center of the central sphere between the tips of the two lander modules, branching out at the four 45 degree angles as suggested by the details on the outer hull. And, of course, there would be another toroidal loop interconnect toward the front of the ship. All of this started from Aridas'
original concepts and cross-sections, but I've taken some considerable creative license with it to try to reconcile all of the exterior modeling work.
I'm taking advantage of some of the space outside the central fuselage for various purposes. Engineering extends into the main engine pylons to port and starboard and also into the saucer area both ventral and dorsal. I've also modified the original concept of zero-gee transit tubes. Instead of two staggered shafts within the fuselage, I'm using four just outside the fuselage where it intersects with the saucer. Two of these tubes are elevator lifts and the other two are switchback gangways. Given that this ship has the ability to land on its tail on a planet's surface, I thought these made more sense. They would be easier to build and film as practical sets, should the opportunity ever arise. And they're no longer taking up valuable space within the fuselage.
This isn't absolutely final, but I'm fairly happy with the direction it's headed.