not sure if this is it...so, i have created 2 stories of a floor plan - one floor is the base plan and the above is the new additions. In this way, I see the grey base plan below when I work on the new additions plan above. then i added new layers - base plan and new additions and saved quickviews.
somehow, these seems rather tedious ...wonder if hotlinking the base plan to the new plan file would be better alternative.
Your method does sound overly complex. (I am assuming from your description that you are using the stories to separate new and existing elements that are on the same actual story.)
The stories in ArchiCAD should be used as intended, to separate the different stories of the building. What I do (and everyone I know does) to distinguish new and existing elements is to put them on different layers and use layer combinations to control when and how they display.
I use different fills for new, existing and demo. I also use a different sequence of pens for the existing elements that corresponds to the pens I use for the new work.
The pen stuff may be a bit of fussy fine tuning, but the layers and fills should do what you want without the complications.
I have just experience something but not sure if this is the 'right' way..
I created interior walls - existing, demo and new.
Wall (2) as demo (instead of existing ) in the base plan layer combination.
Wall (2) as new in the new plan layer combination.
And this seems to work when i switch between base plan and new plan in the layer combination. But I still have to copy and paste Wall (2) twice for demo and new layer. Doesn't sound quite right? does it?
Generally new walls are not built back in the same locations as those demolished. In the rare occasions that this does happen you will have similar walls on different layers. Otherwise the new walls will be drawn on their own layer independently of the demo walls.
You should have a layer combination for the Demo Plan with the new work layers hidden, and another for the Floor Plan with the demo hidden. Remember to set the intersection priorities in each combo so the walls clean up as they should.
It is also helpful to use different fills for demo, existing and new. I use solid black for demo (unusual but effective, it stands out well on the demo drawings); a light grey, solid fill with medium grey outlines for existing; and black outlines with the appropriate material pochés on a white background for the new walls. The same applies for walls, roofs, and floors in section (though I rarely do demo section drawings).