Adding Cupla affects entire plan

[BB boy]

I did do the "create blank 2nd floor". F9 turned on ref floor, drew the exterior walls of the cupola, made them the same as the main ext walls, but funny thing, when I go back right after creating the blank 2nd floor, before drawing any cupola walls and do a perspective view the software has already removed the gable walls over the porch, and raised the end gable louvers to the sky?!?!?! I may try building the cupola roof plains manually. But, I need to look at DJP's you tube. I wanted to fixed it without a lot of xtra help, oh well! I don't have one bit of problem doing it from scratch with a "blank" plan, just 4 exterior walls etc. But the minute I attempt the same thing with my fully drawn final plan it goes haywire!