The following are detailed Deck Plans for the Nova class starship, refit, specifically, the USS Twilight NCC-74413.
Deck One includes the bridge, captain's ready room, officer's quarters, and two small labs.
Deck Two include Captain's Quarters, VIP Quarters, officer's quarters, Crew Mess, and the Rec Room.
Deck Three includes two sickbay complexes, the security complex, the main cargo hold, and various science labs.
Deck Four includes more crew quarters, torpedo tube launchers, two holodecks, the large specialized Waverider Shuttle, and the Main Shuttlebay.
Deck Five includes the Hanger Deck/Shuttlecraft Parking Bay, Cargo Bays 2 & 3, and various engineering systems.
Deck Six includes the Chief Engineer's Cabin, a few crew quarters, upper Main Engineering, and various engineering systems.
Deck Seven Includes Main Engineering (main level), Primary Astrometrics Lab, the Visiting Scientist Lounge, and various engineering subsystems.
Deck Eight includes the Antimatter Pods, the Warp Core emergency ejection systems, landing pads, and the ship's main landing ramp.
These plans were originally designed by Quantum Reality, but redesigned by Lawrence Cohen, to allow for a crew of 80 persons, more labs, and a secondary sickbay complex, for the Twilight is a medical research vessel.
I hope this satisfies your curiousity, and moreso, that you use the above plans in your Star Trek roleplaying game! Enjoy!