This new value should be written to the managed device's registry, following the next policy update via mgspolicy.
4) On an agent device that falls within the specified target, check the registry hive [HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\ManageSoft Corp\ManageSoft\Tracker\CurrentVersion] to see if the new value for PackageDatabaseTypes has been created/updated.
If the affected device(s) belong to a Unix-family OS, you can instead check the config.ini file, available at /var/opt/managesoft/etc by default.
This approach can also be used to apply an agent preference to all WIndows/MacOS/Linux machines.
There are 3 OOTB targets defined within BeaconTarget: target_unix, target_osx and target_windows. Simply use the associated BeaconTargetID for these pre-defined targets to configure a preference for all devices from that OS family.
This approach should not be used for any preferences that can be defined within the FNMS Web UI, as updates through the UI will initiate a policy update when you hit Save and overwrite whatever is currently set.