We Coming back to your questions, I'm sorry but I do not understand what does not work for you. How about if you prepare an example and tell us more about how you would expect the application to behave in this regard? We need working example UPWARD/DOWN extending profile attributes with ditamaps imp...

Subject scheme extending - not working. As soon as in DITA specs we see only SubjectScheme relations, there is not distinct way to accomplish this together with ordinary dita maps. The version XML Editor 21.1, build 2019061404 OSX doesn't seems to support example with baseOS.ditamap and it's extensi...