Opening 3.5 SOAP UI project in Ready API(1.6.0) fails with org.apache.xmlbeans.XmlException

Seeing the below error on opening the 3.5 SOAP UI project in Ready API(1.6.0) . Can you please tell me ways to fix it?

Caused by: org.apache.xmlbeans.XmlException: Element testSuite@http://eviware.com/soapui/config is not a valid soapui-project@http://eviware.com/soapui/config document or a valid substitution.

Thank you