Hi Anthony,
In the latest update to be able to decorate the internal walls you are now creating separate wall objects for each wall , which is great. But there is one important thing which you might want to check if you delete the pillars the wall objects still remain in the hierarchy whereas those should get deleted.
Steps to recreate:
please draw a room like on in the following screenshot, basically create a 4 walls room and then split each wall in the middle and drag the new point out of the room.
https://ibb.co/F67WmCw
Then please delete the same points in the previous step and note the hierarchy there will be extra walls which are no longer required.
Please let me know if you need more details from my side regarding this.