I am afraid that there is no way to fix the ceiling problem, the best thing to do, in my opinion, would be to set the rest of the floor as the same texture that you placed above it. So, if there is a Control Room segment above it, then you should place Control Room Ceiling as the ceiling of the room that the Control Room Segment is above. To rotate entities clockwise and anti-clockwise, press R. To rotate them to be on their side or upside-down, press 1 or 2. As stated above by I has returned, 1-6 can be used here. Hopefully this helps,
Tom
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