DRS add-in does not save Setup parameters after restart

Windows 7/8/10: DRS add-ins must be installed while logged into Windows as as admin user and the app shortcut must be set to 'Run as Administrator for All Users' after installation (Compatibility tab).

Also note user rights settings in this article:

RMS POS user rights (read/write required) - Digital Retail Solutions (kayako.com)

If settings are still not being saved after a restart, you likely need to add the app as an exception in any 3rd party security apps monitoring registry changes.