Adding Cupla affects entire plan

[Kbird]

You have circular Walls JoAnn so shouldn't be any harder to make a round cupola on level 2 blank floor than the square cupola , at least for me with Pro 10 it was exactly the same process except I couldn't freehand a circle wall ,so I used a CAD circle and dragged the wall ( turn snap indicators on if needed) around the circle in two sections so the would join into a circle and rebuilt the roof, gave me the same round roof as the 3rd floor round roof you just showed me.

Curious which Library you used for your stone/wood columns in the post above too .....