spent half a night clearing it up. not that hard apparently. A must have for fun. attached picture of my airfoil rocket fin implementation.
if you prefer jargon and mystery, choose the mystery.scad file. it has the same functionality but more badassness.
use this to replace the original NACA4 airfoil library if had them. Else just add them to //OpenSCAD/libraries.
detail instructions see ancestries. elliptical wing example removed.