IGES 406 type 15 entities to shape association


I am trying to associate 406 entities with the respective objects.

While working with existing IGES files I found that some entities might be grouped and named (for example, for CFD boundary conditions)
Checking the IGES file, I saw that the names are stored as a Type 406, Form 15 entities.

The IGESCAFReader I am using will read and transfer the model, however, only certain entities are actually transfered.
During binding, only shape entities are binded, so that the 406 entities are not used.

I could not understand how to get a link between the 406 entity and its respective parts (mostly of faces).
In other words, which shape entities are part of a group (406 entity).

In a simple approach I would rewrite the transfer function to suit my needs, but I still am unsure how the 406 entity is related to the others.

Thanks in advance,
Best regards,