Feature Recognition Creates Fixed Shape Spline--Cannot Dimension

Hello, I have imported a step file into SolidWorks and used the feature recognition tool. When I try to edit one of the sketches, the program tells me "one of the selected items is a fixed shape spline; currently no relations are available for a fixed shape spline." Is there a way to change the dimensions of this drawing within the part without redoing the drawing?

SolidworksParts And Features