I'm glad Nana was brave enough to venture out! I read your other thread just a minute ago and I'm glad she isn't hurt, I'm sure although she was pretty scared after falling she'll be just fine.
However, that is perfectly normal. Especially because she's not tame, she was probably very stressed flying around where she didn't really know what was going on, which is why she kept crashing into things.
You're absolutely right, though--it'll get much easier for her and less stressful, too, the more she does it.
To bar her way from the kitchen, you can pin a sheet or two to the ceiling so that it hangs down, forming a "barrier" from the exit to the living room. If moving her cage stresses her out that much, I wouldn't do it until she's extremely comfortable with everything (you, flying, etc.)
You can put some perches around the room if you'd like so she sees them as "safe" places to land on, or you can put a rope perch on top of her cage as well as outside the door so she has a place to land when she's too scared to find another place.
I hope it goes more smoothly next time, I'm sure she will slowly start to adjust to her new time outside the cage!