You pass the Dictionary File as the connection path in Crystal.
FreeTable connection path = c:\some\path\to\folder
Dictionary connection path = c:\some\path\to\folder\dictionary.add
You will need to provide the username/password to authenticate to the dictionary.
Once the authentication is successful, the server can un-encrypt the tables for access. When using a Data Dictionary there is no need to use AdsEnableEncryption as it is all handled automatically.
Edgar