Is it difficult question Revit gurus ?

I would try to make your form in two parts, sweep half of each profile at a time. In these cases Revit gets confused when using closed loops as it really wants to make a surface from each profile.

Btw rfo usually gets quiet on the weekend :beer:

Yes it is difficult to answer you.
Keep in mind that, first, Revit is not 100 exact when it comes to create nurbs surfaces. Sometimes fails. This is the reason why the "smarter" designer are using different tools then converting the "thing" to Revit, just because in that way it is faster and reliable.
Second. From the pictures you posted I can predict, without any certainty, that there a couple of spline tool in Revit and it seems to me you picked the wrong one.
Third. These kind of modelling, they may seems simple with Rhino or Sketchup or whatever, but in Revit they are freaking difficult for most people. I would suggest to you to take some advanced modelling classes by the masters if these modelling are your bread and butter.
Fourth, People are here to help you, when they have time or willing to. I do not see paid people from Autodesk here around. I feel that three days to get an answer about a not so hot topic makes you lucky.