Hi to Matt and all.
Eureka !! I managed to configure OCIO on the PC by correcting a wrong data in the Path. I am attaching a test render of the classic Preview. I also corrected the sky where the greenish color was eliminated by changing the color tones on Bluesky Horizon Color (135-135-135) and Bluesky Density Color (Tweaks) at 147-178-255 as recommended.
The last problem awaiting a correction remains, the Exposure Slider which continues to sleep. For the rest I would say that it all works, at least as far as I have seen so far.
Greetings.
Ps. In the various parameters of OCIO I see a lot of adjustments but for now I don't touch them, I just need to have solved the problem with OCIO.