The developer built in the camera calibration as a service function with the latest beta release. Should be simple. I have the camera and an OBDLink MX bluetooth on the way. Will update when I can get it all done.
FORscan 2.3.2 beta, 2016-06-01 release notes
+ Service function "Rear camera calibration" for:
F-150 2011-2013 model year
Edge 2011-2013 model year
Explorer 2011-2013 model year
Flex 2013 model year
Taurus 2013 model year
Lincoln MKX 2011-2013 model year
Lincoln MKS 2013 model year
Lincoln MKT 2013 model year