Yeah, room breaks appear to be completely random. It probably has something to do with how much area their software can consistently generate a cleaning route for in one go. I have one large “room” which was the first area scanned and all the other rooms were areas that were outside the main room but not touching. The virtual walls are not permanent in my app, I’m using iOS so there could be a difference if you use Android. But for me I can click the little button for virtual walls and in there each wall (red box) has two icons, one for resize and the other is a trashcan to delete it. Some I had made real small so I had to make them bigger before I could click on the trashcan icon.
There is another post on the forum that we have going about requesting features for the vacuum app, I’ll post the link here for anyone to check out, add their 2 cents, and help upvote stuff.