Rated it a 3 if you can explain the following plotholes then I'll change

Ask David Campbell - I suspect it was more his writing....

Let all 15 of us that saw this know what really happened would you ?

Exactly. I thought it was (very weakly) implied that the girl was doing it while having those fits ... but she wasn't always alone when she had them. Huh?

(these may be because I had trouble paying attention after a while)

Am I correct in thinking the murdered girl suffered allllll the torments inflicted on others? She was asphyxiated, hanged, drowned, AND beaten?

When/why did this happen? That roommate (Sam, I think) was in a gang or something? And was being driven crazy for ... how long? And his good-natured roommates had no idea?

The disappearing bodies just bugged me in general.

They're coming to get you, Barbara!

I don't know if there's an answer to your questions I thought the light/female ghost was an entity that could do certain things and use the girl just to talk. I believe your 3 it's ok. I rated it 5 because I like 60% of the movie. I think the ending is what kills this movie.

I think the black hair girl didn't do all what we saw and the ghost didn't only possessed the girl she possessed the Australian guy too thats how he ended up in the back of the truck , if she didn't possessed them then she had the power of illusion to make them do what she want thats what we so on how she let Sam to come to the wood and how she made the illusion on him on the bath , and she possessed the black hair girl only during triggering the traps .

in my opinion is wasn't a bad movie it was average 6/10