When I select a wall ( an existing one or one from the root template) the ''edit wall'' tool(?) doesn't appear. I feel so stupid because every tutorial that I've watched, the tool just magically appear and Ican't figure it out for the life of me...
If you are using the Definitive edition Engine then it's normal. The eyes of a child has been changed. The tool is now on a panel (Wall Construction button on top right)
In Definitive Edition Engine, you can find edit wall by doing the following -> Click on a wall piece and go under sidebar. Up at the top, you'll have the Edit Wall Button.
