I was taking apart my Outpost vig because it’s taking up some 1 x 1 tiles I need for another project, and I did this in case I ever wanted to do another something like this.
So you have three essential sections, color coded to make it easier to see:
The blue and red bricks each are one half of the corner. The yellow bricks hold them together. In reality, the halves mesh so perfectly that the yellow bricks aren’t needed, but LDD puts up a fuss without them. With only the colored bricks, you get two SNOT wall sections joined by a 2-wide portion as seen in the right screenshot.
The wall is a completely ‘legal’ build. (which is why I’m even able to do it in LDD in the first place) The only slight error here is that the 1 x 2 tiles on the corner should be slid back away from the corner a little more so that they sit flush with the 1 x 1 tiles.
If you still don’t get it, download the .lxf file.