I really hope you can fix the viewports for V6, when working on renderings it can be a pain that the view only fits the width of the renderer, and ignores the height.
When working on a fixed render output I turn on the safe frame, but this is no little help when it is clipped if the view changes. I use a viewport WallPaper so I can set the model correctly.
I needed to do a product shot photoedit of a model and turned to Brazil and Neon. The photo is in portrait mode, so when I go from normal 4 view to maximzed view Rhino tries to keep the width of the view intact so it zooms in and cuts off “heads and feet”.