Hi Bloodlust, the NURBS modeling in MoI works very differently than the polygons that you've used in Modo. The curves that you show highlighted there are not just plain curves, they are edge curves which are making up the boundaries of faces. Unlike polygon modeling, in NURBS the edge curves do not define a surface, they just mark which areas of the surface are active and inactive. So you can't manipulate an object by yanking it around by individual edges like you do in polygon modeling.

Polygon modeling is kind of like sculpting where you make objects by pushing and pulling on its point cage in 3D space. NURBS modeling is not like that at all - NURBS modeling is more like drawing where you draw key profile curves, then construct your model from those curves. Some curves are used to create basic stock elements like an extrude or revolve, and others are used to cut away material. NURBS modeling is especially strong in the area of mechanical parts where the design can be defined well by 2D profile curves. If you want to make an organic shape that you want to manipulate by bulging out localized areas of it, that's usually better done in polygon modeling than in NURBS modeling.

The inherent way that polygon models are defined means that you can grab small bits of it and yank them around. The inherent way that NURBS models are defined with an "underlying surface" and then trim curves on that surface means you can't do that but what you get instead is the ability to have a hole in the middle of a surface which is why NURBS modeling is much stronger with cutting and boolean operations than polygons.

Hope this helps!

- Michael