I'm actually not sure that the Crown Prosecution Service ought to be issuing clear instructions. It seems backward, but what would be happening then would be that the CPS--essentially anonymous bureaucrats--would be making laws that Parliament could have made, but chose not to. As it stands now, the law (and note that Section 5 doesn't mention nudity and isn't particularly directed toward it) is used as if it said "You can be naked in public, but not if you're too blatant about annoying people", and that's what the CPS tried to clarify.
Think how people would respond if they were asked "Can someone go around naked anywhere, any time?" I think the answer would mostly be, "No, there are times when I'd be really uncomfortable with that, and I want to have a law that enforces it." Then think of what the answer would be to "Do you want to see a person prosecuted if they were seen naked anywhere, under any circumstances?" There I think the answer would be "No" again. So if nudity is going to be prohibited under some conditions but not others, where's the distinction ever going to be made? It has to be left to an evaluation of the situation, which means the law will always be unclear. Most of the time, you can be naked in England or Wales (not Scotland!) and get away with it. But that's because most people, most of the time, choose locations where they don't expect have trouble. Steve Gough is not in that group!
Last year Steve Gough's mother developed dementia and other health problems, and he gave up his naked ways to provide care for her without being taken off to jail. I heard that she died, but not that he ever resumed public nudity. He might have retired permanently, I don't know.