Hi Laurent,
> Michael : i was trying to do the manipulation with the
> object as a solid. that's why i was having troubles.
> we can "only" show points for surfaces and curves ? <...>
Yup, that's correct, except in special cases like with a box solid, since for a simple box case every surface inside the box shares control point locations with every other surface.
In most solids the surface control points do not necessarily align with one another at common edges - that's because edges are often formed by boolean operations which means that they are trim curves that are marking areas of a surface as holes or cut away parts.
Basically when you do a boolean operation in MoI, the full underlying surface does not change, it stays the same and only new trim curves are calculated on it. This is one of the main reasons why booleans work so much better with NURBS than with polygons, because polygons become fragmented into more and more little pieces with each boolean, while NURBS surfaces still stay in large sheets after each boolean.
But on the other hand the NURBS structure using an "underlying surface" and trim curves also means that there is not necessarily control points to edit at just any edge where 2 surfaces are joined to one another. That's because control points belong to the underlying surface and not edges, except in the special case where you have an "untrimmed" surface.
See this FAQ answer for some more description and examples of this issue:
http://moi3d.com/wiki/QUESTIONS_FREQUENTES#Q:_Pourquoi_.22Voir_Points.22_marche_pour_certains_objets_mais_pas_pour_d.27autres.3F
> again i want to thank you for your support since i'm
> not even a customer for now, but i sure will be very
> soon, no more doubts.
No problem, you're welcome! And from the look of your model it seems that you are already making great progress constructing things in MoI - if you just switch to work at not such a small scale you should likely avoid a lot of problems.
- Michael