"The grey ones are in the middle of being sanded down and repainted."
Seriously, I watched several episodes (in regard to the transporter room locations) and the door opposite to the transporter room set appears to be constantly yellow (in "Charlie X" the strange lightning of the corridor makes it look orange).
The Season One door to the engine control room (near the turbolift at the corridor end) is also yellow. But if you want to assign an engineering function to it, you'll have a problem at the end of "Balance of Terror" where the editing clearly suggests that the door in this episode leads to the ship's chapel.
I'm wondering if it were better to apply a process of elimination, i.e. what's not
behind the door. It would appear colored doors neither provide access to crew quarters or medical facilities. Yellow doors might indicate other ship's facilities. Blue doors (e.g. hangar deck) might indicate doors that also serve as bulkheads in case of an emergency.