When you try to apply the config to the newsdocument so that the date is populated with the current date/time automatically (see ) it fails. On the node /hippo:namespaces/myhippoproject/newsdocument/hipposysedit:prototypes/hipposysedit:prototype there is no property "myhippoproject:date". Please make sure it is there, so this config will work. It may be that the property is there in the XML file, but has no value configured. It should be 0001-01-01T13:00:00.000+01:00.
Please check the other document types of the other features too. Are the date properties missing from the prototype too?