VERIFIED SOLUTION i

How to change an XML-based data format in EngageOne Designer

To modify an XML-based data format, you will need to change the sample data to use an XML file containing those fields. This XML file must also have a schema which defines those fields.

1.    Select your Data Format
2.    Select "Tasks"->"Change Sample Data"
3.    Choose the sample data file with the new fields.
4.    Save and Issue the Data Format.
5.    Select "Tasks"->"Generate Dictionary" to update the dictionary and map.
6.    Then choose whether to update the existing ones (probably what you want) or to create new ones.

For the field to be optional you must merely ensure your publication logic does not use it without checking if it is set:
User-added image

Otherwise Doc1 Generate will throw an error if you attempt to use it when it is not there.
Environment Details
Software affected: EngageOne Designer
UPDATED:  September 18, 2017