Good to hear 
Thank you for looking into .
I tried making a blueprint with 4 default spheres, and 4 buoyancy points placed at each sphere.
I then add the ship to the blueprint object as a child (I don’t add it inside the actual blueprint) so that it will inherit transforms.
In setup, the 4 spheres are the only thing physical and buoyant.
I divided the ship, even the hull, into multiple pieces so it would auto-convex better. I’m using the maximum hulls of 24 with 32 verts; It’s now 79 pieces instead of a few.
With setup, I do appear to collide and while it still inherits the transforms from the buoyant spheres without being part of the physics simulation (to my knowledge).
I did however crash unfortunately while testing, not sure from what.
Per-poly however does not work at present, the collision seems to vanish the minute I make it a child of the blueprint spheres.
I still think there are assets that would be better as per-poly, such as the floor. You don’t see people making terrain’s convex xD
So I’m definitely interested in whatever you figure out . =3