Scary and weird!!
This isn't horror; It's simply masochistic shallow weirdness. Also the mechanisms (traps) that magically appear everywhere really make no sense at all. The whole navigation through the house is weird and the main character is strangely shifting between being too calm and panicking. Giving it a 5 because it's not horror, the acting was really not that good and even (as a horror fan) the over-the-top masochism didn't make up for it being scary or gore. All of this kind of made it lose all the tension for me and it made feel empty and unempathetic.
In the theatrical release of the film, Arkin notices Hannah through the window with the Collector going in her direction, and returns to save her. In the alternate ending he looks back at her before running away, leaving her behind.