Problem:

Is it possible to update XDB Server settings without having administrator rights to the PC involved...?

Resolution:

The XDB server gets its settings out of the registry.  

In order to update server settings, the registry must be updated.  

In a  Citrix/WTS installation,  the server settings for a non-service server are stored in the CURRENT_USER section of the registry and can be changed.  

Without Citrix/WTS or with the XDB service, server settings are stored in LOCAL_MACHINE which requires privileges.

The sensible solution to this is to use the XSECADM tool.

XSECADM is a binary , supplied by Micro Focus,  that allows an administrator to attach an access control entry (ACE) to the registry sections pertinent for XDB server configuration.  

There is a "read me" file in MFSQL\\BIN named README.XSECADM that gives some information on how XSECADM can be used by an administrator to give permission to a regular user to update the registry settings.