Hehe
It's the normal way of naval construction ! Some many lines to join :)

You can do that with MoI not now easily now because you can't load the image in background
But with these little plug http://home.insightbb.com/~ryanvm/tinyutilities/vitrite/
you can have your window with transparency !
So open your image in one window launch Moi & Bon Courage :)

If you want a complet tut for make your boat with a Nurb modeleur go there :)
http://www.3drender.com/rhino/boathtml/index.htm

Else if you want a naval boat modeler
the open source Free Ship is excellent !
http://www.freeship.org/