One of my first thoughts watching this movie was that something in the rules of these ghosts changed ... before in the first movie (probably the second too, but I'm not sure) the spirits could only get you if you were in the dark. Once you reach light, they back off. No such rules here, they just seem to come whenever they want. Thought I'd point that out.
If you haven't, I highly recommend watching the original Japanese versions of these. At least watch the original, Ju-on. It's far superior than the remake (and I enjoyed the remake).