The lowest deck shown in the profile is the ship's water supply, which I didn't make a map of.

The lowest mapped deck is the Lower Ccargo Deck. You'll note 3 red domed towers at the center of the main deck, shown in the illustration. Those areas are separated from the rest of each deck as a part of those structures. The larger central tower is the Temple to Lolth. The top or left side tower is the Fighter Academy, while the other side tower is the Wizard's Academy. In the forward (left side) area are stairs up and down to access other decks. Aft of that access to the tower's cellar levels, a trackway around the circumference of the abdomen. Aft is part of the water filtration system, as the ship's water is 'recycled'.

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Next deck is the Helm and Main Cargo Deck. Helm at fore (far left side), followed by storage areas for cargo (found across this deck), then Navigation, behind which is the stairs accessing other decks. Following this is secured access to the cellars of the towers (higher level), and at aft is the steering control for the sails. The interior space is 800 feet long, so yes, this is a big ship - I included the grid to show scale...

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