Relaxed CNDs - Unable to commit new document type

1. Start quick start, navigate to documents >> configuration
2. Create a new Namespace
3. Create one or more document types
4. Click on commit

Issue - Below exception is thrown in separate dialog.
javax.jcr.nodetype.ConstraintViolationException: /hippo:namespaces/rlxcnds/basedocument/hipposysedit:prototypes/hipposysedit:prototype[2]: mandatory property

lastModifiedBy does not exist

Then when I try to create a new namespace it throws "An error occurred, please retry." (exception file attached)