I struggled with this, the trailers really didn't give a good impression of what to expect.
I did like the nods to the games, the puzzles and exploration from area to area, counting the bullets and discovering new weapons. The atmosphere was good at times, and some of the monster designs were pretty cool.
Unfortunately beyond that it all felt extremely disjointed, and it borders more on being a slapstick comedy than it does a horror, the tone of the humour mostly didn't land for me. The protagonist didn't help either, he just came across as insufferably awkward and incompetent throughout the entire movie.
I've very mixed feelings about it overall, I don't regret having watched it and it's short enough that the parts I didn't get on with didn't bother me too much. That said, in hindsight I would have rather watched it at home on the couch over taking a trip to the cinema.
5.5-6.0 out of 10 for me.