I have a frame wall and CMU wall that I'm trying to get to just connect properly, I'm just trying to get the frame wall with the window to match the form of the lines in red. Everything I try just gives a similar variation to where just a point of them connects together. I tried to add a polyline at the end and use it as a modifier and I've trying editing in place while adding vertexes, but nothing works to get the frame wall to make that shape.
Are you only showing components, and not Shrink Wrap? Are the Walls multi-component?
Automatic cleanup can give you the outline you seek, but it will not stop the "fat" horizontal Wall vertically, as illustrated by the image below, where an object-level override has turned on the Shrinkwrap Hatch of the horizontal Wall to illustrate its extent.
You can get the wider Wall to stop vertically, by editing the cleanup in place. Edit the cleanup of the angled Wall and add a Vertex to the right of the lower Wall face intersection point and below the upper Wall face intersection point.
I was lazy in my first response, and just used Standard Walls for all of the Walls. Using Stud and CMU Walls, I get the results that you did using automatic cleanup. Editing cleanup in place is still the way to get what you want.
Here are the Stud and CMU Walls, along with two lines (dashed, lavender) that I added to make the edit in place easier. This time, edit the CMU (wider) Wall first, and pull back the CMU to the vertical line. (You can do the Stud Wall first, but then you have to deal with annoying messages about it overlapping a component of greater priority. Since you have to do both anyway, it is easier to do the CMU Wall first.) Then edit the Stud Wall cleanup, extending the upper Vertex to the intersection of the two reference lines, then adding a Vertex at the intersection of the vertical line and the lower face of the CMU Wall.
I attached the file in which I was working, which includes the Walls from both conditions.
