You can use the ConfigKeyFormat option to customize the luggage tag for displaying one or more custom attribute fields (see (10.8.0_WDW-en_US) imEMM.config).
For example, you may want to configure the luggage tag to display only the Matter Number, or to show the Client, Engagement, and Year fields. The following table provides a mapping of custom attributes to their IDs, which need to be used while setting the value for the ConfigKeyFormat option.