After you click on the "Make Available to clients" button you can either check the "Date Modified" property of the "ldappl3.ini" file in the "C:\Program Files (x86)\LANDesk\ManagementSuite\ldlogon" path of the core server to see if this has been updated:
or alternatively open the same file and look for your newly added registry key in it under the "Registry Info" section.
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