I've been at this night and day for several days, trying to learn the software... watching as many videos and tutorials as I can, and felt like I was doing pretty well for a total beginner. (I have no architecture or construction or house design background.)
Suddenly this afternoon half of my walls disappeared and my roof was on the ground.
This morning I had a perfect turret (I used a curved wall, not aware if there is a better option) and now I know to screenshot when something looks the way I want it to so that I can show it when I ask questions.
If anyone does reply... thank you in advance, and please be gentle. I am in the very beginning stages of learning, and I'm sure it looks a mess to experienced people.