As other reviewers have pointed out, the film presents us with a disparate group of people each isolated in their own way in a remote and challenging landscape. All have their own issues, and consequently aren't automatically brought together by the mysterious problems that slowly arise: instead they are confused and divided, unlike the outcome in some other films of this type. That, together with a lot of intentional vaguerie, gives the film dimensions that make it interesting and discussion-worthy to some. However I think most people, certainly those looking for a tight plot that comes together in a definite answer in the end, are going to be frustrated and irritated by the story and its "resolution."
The acting is good, and though I wasn't particularly impressed by the heroic "ex-con judged by his reputation" stereotype, it was played perfectly competently by Steven Vidler, likewise the stressed-out obsessed cop well played by Vincent Gil; the nature of the plot is such that random and uncoordinated behaviour actually contributes to where the story is going - in the end a government conspiracy is vaguely alluded to, but its nature or intent is left deliberately vague (in the NetFlix version *I* saw anyway.)
I wasn't particularly impressed by the "suspense," which is achieved by a lot of jump cuts of frenetic behaviour in dark rooms. Things happen, something else happens, the action shifts... The film eventually ends...
I love the movies of Peter Weir, and Director Rolf de Heer is obviously heavily influenced by the opacity of his countryman's films. Weir, however, is alluding to semi-mystical powers of nature, which has nothing to do with whatever is being encountered at Raven's Gate.