So, I was working on my base and I accidently raised the floor to the ceiling... I haven't been able to figure out how to lower it again. After trying to do several things, I did find out that there is a <ctrl><z> for undo, but it was after I did to many other edits trying to fix my problem. In the past, I normally just delete the room and start over when I encounter this issue. However, I am hoping that someone will have a better solution. 😞