Adding Cupla affects entire plan

[BB boy]

Rich, I know that ought to make sense, however if you look at the snips I added, I did the cupola both ways on the practice plan, didn't affect the roof at all. Tried it on my working plan (again the practice plan has no walls built) but doesn't matter which way I turn the cupola.....bang everything goes to !?!?!?! And I forgot to mention, that snip one I had not done the cupola at all, I had only opened my working plan-went to build 2nd floor (blank 2nd floor) per he tutorial, then did perspective camera to see if anything changed and BANG! There go the gable lovers, and the gables disappear!?!???!!!