Gero,
Wow! that is a cool video. The big guys have the resources needed to do this type of thing - a software suite, large scale ploting table, CNC routers... and so forth. I on the other hand have some sandpaper and a limited amount of time.
Concerning hydrostatic calculations, I am old school and do this with a planimiter and using simpson's rule or trapezodial rule. One advantage of developing hull lines as a family of ellipse sections is that unlike tortured plywood or constant camber, you do end up with true lofted surface. This helps greatly in prefabricating bulkheads and interior structural joinery. Try this for pictures:

http://www2.snapfish.com/photolibrary/t_=130509924
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