Viewpoint 2.5.6 build 56. Platform: Windows 8.1 64 bit. Also installed Photoshop & Lightroom CC 2015, & OpticsPro 10.
Whether launched as a standalone program or a plugin from Photoshop, Viewpoint crashes when loading the CR2 that a TIFF is derived from. In this instance, the CR2 contains EXIF metadata on a photo taken with an EF 11-24mm f/4L. I suspect Viewpoint does not have the data for the automated distortion correction, unlike OpticsPro 10 (where I can download the lens modules myself from within the program). An exception occurs and Viewpoint closes with the message "DxO Viewpoint 2 must close because of an unhandled exception."