Error: Missing attribute <REF_FIELD> for Field: <TRANSFORMFIELD name>.
The specified TRANSFORMFIELD element in a Router transformation is missing a REF_FIELD attribute or contains a value for the REF_FIELD attribute that does not match a TRANSFORMFIELD element in the XML file.
Edit the XML file and enter a REF_FIELD attribute. Make sure the REF_FIELD attribute matches the name of a TRANSFORMFIELD element. Or, export the object again and then import it.