!!This plugin is here for backwards compatibility and should no longer be used.  The Preferences, [User Config] allows for DB integration and is the only supported method since CrushFTP v5 and above.
The CrushSQL plugin lets you integrate a SQL DB with CrushFTP.  This plugin is from CrushFTP 4, but will still work.  CrushFTP 5 has built in support for integrating with SQL.  The CrushFTP 5 built in support allows the [User Manager] to be used with the SQL as well.  This plugin is just read only, and the User Manager cannot see this plugin's users.