I know the door icon has been slimmed down a ton, but I still find myself clicking dozens of times to get the correct wall to become a door. I just finished running a session in this dungeon, which I don’t think is very wild in it’s design (considering it’s from a WoTC Module). And this is what it looks like trying to turn 3 walls into doors.
Not sure if this workaround will do the trick for you, but the last time I stumbled into this I decided to move a DL point, place the door, and then return the DL point back to its position.
Something like this: