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Use the Return Variable and Send Message Branch Action Series when working with BAPIs and RFCs. These will help you catch serious problems like ABAP exceptions and communication errors. Be aware that some BAPIs / RFCs use ABAP exceptions even to return good information! In these cases, you will need to analyze the Return Variable in the Send Message Branch Action Series and decide how to proceed.
Be sure to set appropriate Workset Table Key Fields on the Workset Tables associated with any Table parameters. The Wizard will create the Workset Tables for you, but it's up to you to understand the data and flesh out the Workset structure properly with any parent-child relationships and key fields.
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