That does not look like the arch showing in section, it looks like a reveal (see your sill condition) and maybe a very odd composite wall that seems to have insulation as the interior face above the window. Tell me how did get the interior skin to stop and not cover the upper portion of wall? Complex Profile?
Very strange that the window (or weather closure rollup) can slice the brick face like that, may not be easy to build well. I'm guessing the rollup extends all the way to the interior face? So we aren't seeing exactly what the wall is doing. Remake this without the rollup, it will help diagnose the issue. (I've seen "rollups"in Europe alot, but I don't know their proper name.) Is that an AC window, an add-on, your GDL, or a purchased library part?
Insulation in plan has been answered for pre-AC14 elsewhere in these forums, in 14 you can do it automatically in wall composites.
Please include a signature in your profile that tells us what AC version and OS you are using.
Snap
Rubia Torres
