Hi Cam,
So I played with your plan file, and noted that you have some extra roof planes. I deleted them, turned off auto roof rebuild, and changed the slope of the shed roof as Eric mentioned in his earlier post.
I attached the revised file so that you can see what I did. You may be able to apply these techniques to your project.
778952992_Piper_3rdRound2_4_2021 (1).plan