Now available in Application Manager, direct links:
Service Pack 2 resolves an issue opening and appending multiple files in a single operation. The Service Pack also resolves issues identified in our Point Cloud support, Autodesk Rendering, Quantification, Clash Detective, and interoperability.
Readme and install links:
Main Autodesk page:
Navisworks 2015 Service Pack 2 | Navisworks Products | Autodesk Knowledge Network