In the DomToXML_TableMapping_v3 double click on importcalling and export the value of refnr also to importrefnr.
The Import functionality, built in Mendix based on an XSD, requires that all the element 'ImportRefNr' are filled with a value. If that isn't the case Mendix will give you this error and cancel the import.
In your XML an element 'ImportRefNr' (The path to the element is:TableMappingList|TableMappings|ImportCall_TableMapping|ImportCall|ImportRefNr attribute: DatabaseReplication.ImportCall.ImportRefNr) isn't filled with a value. You should search in the XML for the subelement and maybe remove the parent element 'ImportCall'.
Were you able to find a solution?
I'm facing same issue:
While trying to export TM from Database Replication of Table Mapping where there is Reference to other entity used I'm getting this error.