Autodesk Robot Structural Analysis

[#1]

I believe we should be able to save part of the structure using Geometry>Structure>Save substructure to perform calculations and later update the main structure.  

However I notice that all columns, beams and floors etc. are converted to bars and panels when I save the substructure.  Changing them back to columns and beams gives me an warning that my results are out-of-date ... 

Is there a way of saving part of the structure and calculating required and provided reinforcement?

[#2]

I'm sorry but I don't understand what actually happened. The calculations of reinforcement for both panels and bars is based on the values of internal forces which as saved along with the sub-structure and set of design parameters assigned to these objects which can be changed at any time and such change should not influence the status of the results. Could you make some screen captures that show both your actions and their results please?