Add new User Group with SAP Plant Connectivity (PCo) in SAP DM

[nwalter1]

Hello,

I established a successful connection from SAP DM over Cloud Connector to SAP Plant Connectivity via certificates signed by our CA.

I set System Mapping Configuration to "Principal type: None". If I understand correctly that means, I can define a User Group with rights to perform actions on PCo side (according Help Portal User-Groups ) 

I followed the steps of the Help Portal, but in PCo configuration under User Group "Add":

I can't see any Items in the list: 

Via DevTools I see the request when I click on Go, but the response is empty: 

Has someone every created User Groups and can help me out? 

BR
Nico