Can I assume the circle on the cylinder is just for convenience? In other words if you sketched a circle on a plane and used that as the origin, would it be the same thing? If you are using a trajpar then I assume you are trying to create some kind of "helical" feature? Not necessarily a true helix but some type of feature that is rising while it's running.
You may be better off creating an explicit drive curve and the start curves, internalcurves (if needed)and ending curves then use boundary surfaces to create the solid. VSS with trajpar is a resultant method of creating geometry whereasdeveloping the geometry gives much more control if the features are not "simple" stuff.
Sketch a picture of the ultimate goal and post it. From there it can be determined what method may work best.