Create Distributed Attribute Group, the UDET

The task only differ from creating a regular User Defined Element Type (UDET) in one aspect, and that is that the UDET intended for use as a distributed attribute group must be based on the XPITEM element type.

You must create the UDETs to be used as distributed attribute groups, these UDETs needs to be defined with XPITEM as their basetype, then the attributes must be created.