Hi, Costek. Greetings from Spain. I bought the plans for a Vacationer in 2000, but have never started building it due to lack of space. However, I have made many models with Rhinoceros and when doing the calculations I have always encountered the same problem as you, what is the waterline? Without that you can't study stability or displacement or anything. That is why I am writing to you now: Did you build your boat, or just the model? Greetings.