The Split tasks in the RIC allow segmentation of large payloads into smaller ones. Split tasks occur after Compare tasks.
As an example for Customers: Set the Payload section to MI4CustomersWithMessagePayload.xml Parent Element Name: MI4MessagePayload Repeating Element Name: MI4Customer Segment Size: 100 (this can be changed).
After a Split task, you'll have to translate the payload into MI4Message XML, to get a new MessageGUID. In the Payload section, add in [/MI4Message/MI4MessagePayload/MI4Customer] to insert the whole payload from the segmented source.