For those aspiring (or is it perspiring?) starship engineers regardless of the game system you're using, I've put up FASA's Designing in Detail guidelines for doing deckplans which make sense. Too bad FASA's artists didn't use them, but whaddaya gonna do?
Click on the Star Trek: Relic link below, scroll down to A Gaming Miscellaney, then scroll down again to get to the link Designing Deckplans in Detail. Enjoy!