vague warnings
I haven't seen this movie, but one part from the novel that always annoyed me was when whatever force tried to warn Louis about the barrier did so in such a vague way. They sent Pascow back in a dream state to tell Louis not to cross the barrier. Why not tell Louis "the evil burial ground is trying to have your child killed. Built a fence for your front yard so he won't get run down in the rud."
And I know, the common retort is "because then there wouldn't be a movie". I don't accept that. If the opposing force that sent Pascow back has enough power to warn but not interfere, it should have the sense enough to not be vague about it.