Soon after, I had clsurf up and running. It required some massage in order to work with a recent OpenCL version:
#define CL_USE_DEPRECATED_OPENCL_1_1_APISBut it eventually compiled and ran successfully using CPU device (I don't have a dedicated GPU on my dev computer) to produce this lovely image:
|Lena with SURF features marked with clsurf
Not bad for a midnight hack!