ARIS - SHARE YOUR IDEAS
When modelling with ARIS certain objects are administrated centrally - e.g. organisation units and applikations. Designer Users should not be allowed to change the content. These objects need to be locked by ARIS Admin.
Would having those Objects in a Folder that the Users, using User Groups, only have Read Access to not provide what you are looking for? I have implemented things this way and this provides (I think) what you are asking for.