Simply put, I hoped it would look better (more 'piratey' I guess) than it did. It's too long, too narrow and too tall. I really hoped to be able to widen the hull a bit, but the hull geometry doesn't match standard LEGO geometry very well (eg the sides of the hull are off-vertical, but they are far more vertical than a tall slope).
The design limitations I used were simple - no pirate parts. (Just to see if it could be done).
It is... I borrowed the calico sails from l'Ambassador Rouge for the pics, but didn't have a gaff sail/spanker to suit (and didn't want to modify one either).
That's the one! And the fireboat set provides a reasonable number of 2x2x2 tall slopes - a most useful piece for ship building.
No, it just means the superstructure is way too heavy for the bouancy of the hull.
Not directly, but things can be attached by way of a technic axle and parts - the motor that comes with the fireboat set attaches to the hull via a technic axle included in the motor moulding.
Well, that is the nature of speculations ;-)
Um, no, not the least because I don't have a bath tub. :-D
However, I have observed the performance of the fireboat model in a swimming pool, and I can compare how much the Nonlibre Billet weighs compared to the standard model, and I can conclude to my complete satisfaction that it is too heavy to float, in any reasonable way.
Bouancy is about mass and volume - what the Nonlibre Billet needs is more volume, not more mass.