HI there,
You may have abandoned this question since there were no responses thus far, but as a long time MainStage user I thought I'd chime in just to give you some confirmation.
As you may have already discovered, MainStage doesn't work this way. The Layout won't pull up a VI's display page - the layout is used for drawing screen controls that resemble controls you have on your current keyboards. Once they are matched in Layout mode, you can assign those on screen controls to controls within your VI's.
