A ComplexRelation is used to show e special relation between DataRelations connected to the same DataEntity. If for example a DataEntity can have relation to one of three other DataEntities, DataRelations are drawn to all three DataEntities. In addition to that a ComplexRelation is created and placed on the diagram.
The DataRelation covered by the ComplexRelation is referenced from a link list in the ComplexRelation. It is also recommended to draw the ComplexRelation on the diagram.
Currently there is no automatic synchronization between the two tasks.