True. And it depends on how logically the globals were set up in the first place as to whether the mapped tables/classes can reflect a sensible logical schema. You could still map them without that but it wouldn't be great for usability.

If you're using IRIS to transform other message formats to and from FHIR using DTLs/Apis or some other way then you'll need to implement the profiles yourself.  You can create your own DTLs based on the ones in IRIS to implement the profile constraints and extensions or you can code it yourself.