Eureka - I found the issue.   In preparing a sample plan from a new template file for this discussion (a file free of my manipulation) I discovered that the issue has nothing to do with a stepped wall as I may have implied in my earlier post (or maybe I didn't).  As you can see from the snapshot with the green siding the foundation wall is showing a gap the depth of the slab, the gap is the result of my pulling the concrete wall down under the terrain.  This is when I realized it wasn'