What this image shows you are the kind of 2D line images SketchUp can export. What this means is that it will allow me to recreate exact line drawings when it comes time to make the schematics. And because I'm working from an existing model I don't have to "best guess" what something is supposed to look like from different angles--SketchUp will have done that with precision already for me. Note, too, that there are some things that don't appear as lines (notably on the side of the dorsal) because those edges actually have rounded edges. A curve appears only if it appears as an edge from the p.o.v. of the viewer, in this case as seen directly in side elevation. In my models I try to incorporate a certain level of detail including edges that could actually be rounded.
Regarding window arrangement I must confess to a degree of fudging in terms of deck levels. I didn't do any sort of actual cross section to lay things out with precision. Rather I spaced out decks in a general way and then slapped in some windows along those guidelines with the general assumption the windows would be a bit more than halfway up the bulkheads. I did assume the possibility of not all decks being having the same ceiling height and between decks structures (floors/ceiling) would have a measure of mechanicals between them. I think that allows me the flexibility to rationalize why windows levels might not all be evenly spaced. One thing in particular I quite like with this kind of graphic is that it can show what something like signage and lettering correctly looks like in a 2D image. Lettering on a cylinder would actually look just a bit squashed. Seen from above the ship's name on the saucer wouldn't look straight but actually slightly curved because it's laying on a compound curve surface angling away from your p.o.v.