So I wanted the asian wall for my custom world so I extracted the one from Shangsimla and turned it into the single layer wall like in the picture. (i thought...) and I have been playing the world with it for like 2 years. Recently I was trying to put a lot near it and the game was saying that it is unroutable area... It was weird because it was just flat land. So I recently reopened the world file that I had exported and found out that the wall that I edited looked like in the picture in CAW. I put the original Shangsimla one right next to it so I can compare. Do you guys see the red border line of the original double wall is still there? That area blocks the routable area as you can see.

So here are my questions..
1. In edit town mode of my current save, I was trying to move that wall away and put the lot on that exact spot, but I couldn't put any lot on the spot that wall used to be at. Is it always like that? Once you put objects like those and export, that area will be forever unroutable even if you get rid of the objects in edit town mode?
2. I would like to work on my custom wall again and get rid of that original trace of the wall. When I was editing the wall, I don't remember I saw that area but it turned out to be still there even thought I removed the wall part. Can anyone help me with removing that part? What did I miss..?

Can you find that wall listed in the side panel for your world? The one that lists all your layers and objects? If you can you see it listed, maybe you can delete it using the panel (select name, then delete object) instead of the preview window.