It appears, from reading Oracle Warehouse Builder 11gR2: Feature Groups, Licensing and Feature Usage Management, that schedules or multiple configurations requires Oracle Warehouse Builder Enterprise ETL license.
If you have OWB Core, then scheduling a OWB mapping has to be done using Enterprise Manger Grid Control, Database Control or any other application that can manage Oracle Database Jobs.
Moreover, in the project can be only one Configuration module. That means for switching from development environment to production, you can not just switch default configuration to other predefined configuration. You need to edit DEFAULT_CONFIGURATION and change credentials manually each time.