From poly-surfaces to subdivision with GH

Hi. I am not being able to get the Catmull Clark node give me a smoother outcome.

The cubes go inwards on the “hip” / middle. I would like to get a smoother version of the nurbs.
It might be also related with the Constant Quads node. I can see that the top surfaces and bottom are getting much more polygons than the sides of each cube.
Could it be that?

I am using a file that another user helped me with. I am new in GH.
I attached the file. (29.8 KB) (23.6 KB)

Thanks so much. I was using Mesh Join command which I thought it was performing as Weld .

Thanks for your insights.

I have another question regarding the file, but not the same situation. Should I make a new post or I can ask you here ?