I am trying to use the OpenCV library for some image processing inside my Windows 8 Store app using C++/CX. I am able to build the OpenCV library using Visual C++ 2012 but
We are working on enabling OpenCV with the new Phone and Store build of CMake. In the meantime have you looked at http://github.com/msopentech/openCV. This has instructions on building OpenCV for WinRT.