you can use the "advanced" roof cutting tool under design > roof extras > crop to single-plane roof. all you do basically is make a roof thats slanted the way you want then mark the window and roof and then go in the setting i mentioned above. ive ma...

absolutelly agree. when reading the documentation im left here just wondering what i just read and it basically didnt help at all. im herby reviving this post so it will get updated

have you tried the align tool  i tried with your file and it worked.here is how i did it- aligned the two outer walls where the issue was- then aligned the vertical wall into the other outer walls.