Is it possible to change a cross-section property (torsional constant) of a CS created in MODELER, without using "Beam, CS values" element type?

Hello community,

I am trying to edit the cross-sectional properties of the elements of a grillage model, in order to simulate the torsional stiffness of a multicellular deck. I have created the web sections using MODELER and assigned them appropriately.

Now I look to artificially change the torsional constant and vertical shear area without losing the CS(Begin) / CS(End) definition in the cross-section assignments (and the reference points I need to perform stress checks). Using the "Beam, CS values" in the cross-section assignment to edit the torsional constant dismisses the MODELER cross-section assignment and the reference points are thus lost.

Is it at all possible to edit a cross-section property without losing the rest of the MODELER definitions and the remaining calculated mechanical properties?

Thanks everyone in advance for any input you can give me.