Set your pivot points a constant distance from a reference point such as the adjacent wall. I usually put them right on the wall. Set matching elevations. Use the pet palette to make a cut out in the main roof for the door roof and use the "Command click" method to automatically align the ridges and valleys.
Some times it is easiest to use the auto hip roof tool and adjust from there.
Command Click you say? Select the one of roofs and command click on the opposite roof ridge and it should jump to the intersect position. Repeat for he other roof.
Cheers John
John Hyland : ARINA : www.arina.biz
User ver 4 to 12 - Jumped to v22 - so many options and settings!!!
OSX 10.15.6 [Catalina] : Archicad 22 : 15" MacBook Pro 2019 [/size]