I feel that a flaw like that is insignificant. The only thing it points out is that someone is using a helicopter to make a film. A director like Kubrick, who along with half the world, would have easily picked that up. If the shadow was there, then either Kubrick wanted it there or felt that it was insignificant and wouldn't, as it shouldn't, be held against him as any form of a serious director flaw. Not that it should be there, but Kubrick knew it was there. It wasn't a "slip-up".
This is a real sloppy mistake. There is no way the director thought that it should be in it. He was probably being to anal about other stuff to put in the effort to make sure the intro was done correctly. I don't care how good of a movie it is you are dumb for pretending that he is so good that it must be done on purpose.
Kubrick's version was great, a classic. It was not, however, true to the novel. King did the mini-series in order to create a film that was exactly like the novel, not an interpretation of it. Since it's his story, born of his imagination, I can't imagine you'd criticize him for that. Without him, there would've been no Kubrick film.
I know that a few years ago, they decided to make a series of the Shining involving Stephen King called Stephen King's the Shining and let me tell you, I think it was a cake walk compared to the original from 1980. The Stanley Kubrick film starring Jack Nicholson was much better. Stephen King should have left it alone, even though he himself only probably hated the movie.