The reason that the rescue account name is saved as the default value of the AMServerManagerAccount key and not as a string value is that it is possible to set security for a registry key in Windows. Doing so is highly recommended because unauthorized access to this registry key could compromise the security of your system.
To secure the rescue account:
HKEY_LOCAL_MACHINE\SOFTWARE\Cyco\AutoManager Meridian\CurrentVersion\OML\AMServerManagerAccount
Related concepts
About Meridian user administration
Understanding Meridian role-based security
Related tasks
Creating and editing user accounts