open the Database tab expand the connection and tables section, does the database tab list the table you want to use? If not, double check that the connection is connecting to the correct database.
Since you want to use your own table, in the security assist wizard set the application type to New From Blank, and select your table from the tables list.
the other application presets are based on the tables that will be created. using your own table, you need to start a new preset.