When creating a metadata against a PostgreSQL database using the Configuration Wizard, a metadata under the default schema, public, is created. There is no option to specify the schema to be used in the Configuration Wizard. Use the following workaround to specify the schema.
You can add an Initialization String to specify the used schema when creating a DSN.
set search_path to 'test';

odbc.inifile.
ConnSettings=SET SEARCH_PATH to 'test'
InitializationString=SET SEARCH_PATH to 'test'
After this change, when creating a metadata via the Configuration Wizard, the test schema will be used.