In Zevachim 33a, it’s stated that a new door could not be added to the Temple courtyard, because the Divine plans did not provide for the proposed door.
In Zevachim 35a, it’s stated that the Kohanim kept their garments clean by walking on raised stones that were set upon the Courtyard floor.
Why were the stones not considered a deviation from the Divine plans for the Temple?
The stones weren’t a fixture. The doors would’ve been a fixture.
The stones were there as chairs
The stones were an extension of the floor, so halachicly, it is considered no change at all.
I think ZTA is right. As long as they’re firmly attached, the itztaba’os are lichcoirah a chelek of the azarah/ritzpah, while a door will be a new pesach, not just another piece of wall.