When I draw a draft object with snap help of an Arch object, the Draft Object get support of Arch Object so we can't use the Draft object of base to a Substraction object (Extrude) for this Arch object. I get a DAG error.
Workaround is to create Draft object in a clear area without use of snap mode then place the Draft object...
Have you the same behavior ?
I was thinking about a feature (at least I don't if it's already here) for Add/Remove component tools.
Like the window tool make a hole in Arch Object, the Add/remove buttons can add an extrusion or make a pocket in the Arch object from a Sketch. It's keep the Arch object at top levels.
I'm starting the hard work (machining) on this project
It's a pleasure to model it in FC