Exciting, spooky concept, Arthur Payne.

I think your logline needs a little work (just a little). Here's a logline suggestion: "When a group of high school gamers plays a computer game inside a haunted mortuary, the game starts killing the participants, forcing a plucky teenager to overcome her greatest fear and solve the game before she and her brother become the next victims."

Or this: "When a computer game starts killing high school gamers inside a haunted mortuary, a plucky teenager tries to (or "attempts to") overcome her greatest fear and solve the game before she and her brother become the next victims."

Also, there are extra spaces before "When" in your logline.