Symptoms
Error when Move Document method is executed on a SharePoint library SmartObject
Diagnoses
We were able to reproduce this error using a subsite of a wildcard site collection - i.e. http://portal.denallix.com/sites/WildcardsiteCollection/Subsite
Resolution
We have logged it as a bug and linked this ticket to TFS item _548720 - SharePoint Content Broker Document Library: Move document to folder in same library, on a sub site on a wildcard site generates Object ref error.
This will be addressed and shipped with future release of the K2 software.