The strange case of the sliding wall door

One of the big upgrades in build mode with The Sims 4 is the ability to move around and plop down fully made rooms.  I tried using this feature to build a house only from premade rooms, but something still isn't quite right...

The door from the dining room to the kitchen didn't update the wall well enough.  This house was built only with premade rooms that are preinstalled with the base game, so this isn't a custom content issue.  On seeing this, I tried moving the door and furniture around, but it wouldn't display the open archway correctly no matter what I did.  The sims living here didn't seem to mind since they walked through the phantom wall section without any problems.