1. Flight deck, right for’ard, and not on either of the decks strictly speaking, since it’s in the nose of the craft in what amounts to a transparent dome. The pilot’s command seat is, essentially, centered exactly on the fore-to-aft drive axis. Openings above and below provide access to both decks.
2. The common area, on the upper deck, ending in the for’ard upper level module access. Includes two stacked crew pods (a) to port, for the crew to sleep; a smart-table (b) for miscellaneous work, administration, and recreation purposes, and (c) a galley and fab unit to starboard…
3. …for’ard of the ‘fresher.
4. Most of the lower deck is a single compartment, which includes avionics equipment and canned life support (to starboard) and racked stowage space (to port), although most of the port side is taken up by…
5. …the airlock, an unusual three-door design that doubles as the for’ard lower level module access as well as the boarding airlock and an airlock providing convenient access to the module volume when no module is installed.
6. The airlock/aft lower level module access provides access to the engineering hull when no module is installed. It leads into…
7. The engineering section, which is primarily a single large chamber. The upper deck only exists as a catwalk running around the perimeter of the chamber, and the aft upper level module access is a simple spacetight door that cannot be opened when no module is installed. Primarily notable in the engineering section are (a) the vector control core and reaction wheels, (b) the port and starboard auxiliary power reactors, and (c) the robot hotel, with scuttle access to the propulsion bus for external maintenance mechs.
(Note: The Nelyn uses canned life support because it’s basically a local ship; the vast majority of them in use are not in roles that require them to ever venture very far from a source of resupply. Those who’d like to use their Nelyn for a long interplanetary or even interstellar voyage, on the other hand, aren’t left out; they can simply plug in the “accommodation” or “luxury suite” module, say, that by design comes with its own regenerative life support and possibly even hydroponics…)