The custom action response thing is a bug in rasa 1.5, we are looking it aleady!
As for the issue above, I believe it is unrelated to the UserWarning: Could not find endpoint file at path ‘endpoints.yml’: File ‘/app/endpoints.yml’ does not exist… f"Could not find endpoint file at path ‘{config.endpoints_path}’:\n{e}." This is a log that should not be there, but I believe the endpoints are actually found correctly. I have never seen the long OMP error you posted before. Was anything actually going wrong in 0.22?