"Ceiling values may not be changed..."

[David J. Potter]

the default setting for the floor height of the first floor is always "zero inches". The other floor heights are set relative to that stable datum for the basement and upper floors.

Explain exactly what you did or tried to do that has resulted in unwanted results please?

You set the majority floor and ceiling height in "Default Settings - Floor - Structure Tab - Ceiling and Floor Heights" per floor, if you do not change those "out of the box" settings the software will ALWAYS tend to try to follow whatever those values are set to in Default Settings and can be counted upon to undo or override any local room dialog box settings. The software follows its Default settings and NOTHING else, ever.

DJP