Unfortunately, he problem is that the left hand image does indeed have a "in from baseline" value of 0, as shown in the image. You mentioned you thought it was greater than zero, which by the image, should be true... but it isn't what is entered, and that is why I'm making this post.
When I increase the in from baseline value from 0 to 12, it increases the height of the slope transition point even more--compounding the problem. It is almost as if there is a fixed height at which the slope must change regardless of dormer height. The program basically thinks my 7' dormer wall is 9' tall and it also thinks my 5.5' dormer wall is 9' tall--why 9'?
For visual reference, it is hard to tell, but you can see in both images the transition point is the same absolute height of 240". That issue happens if i enter 12 or 0 from baseline. 12 is just even higher than 0 for both images