I was getting closer to zero copy buffers and their features (both device-resident and host-resident zero copy buffers).
Even if on my system the Transfer Overlap sample runs fine, with no problems about buffer flags, I realized that creating a buffer from scratch in another VS project with the flag CL_MEM_USE_PERSISTENT_MEM_AMD results as an error (flag not defined).
Since my laptop configuration should support zero copy buffer (GPU: AMD Radeon HD R9M290X (GCN), Driver Version: 1268.1 (VM), OS: Win7, System Architecture: 64-bit machine), I hardly believed the CL_MEM_USE_PERSISTENT_MEM_AMD flag was an option already coded in OpenCL. I checked in the cl.h header file and there's no declaration about it.
So, it's just a matter of declaring a struct and all the flags to comprise the CL_MEM_USE_PERSISTENT_MEM_AMD one (as in the Transfer Overlap sample), or I'm missing something else (like paths or other header files attached to that sample and that have to be included in the VS project for working with the CL_MEM_USE_PERSISTENT_MEM_AMD flag available)?