I like the concept, but there are some problems: It's too easy. It's obvious who the killer is the minute they start talking, and there's too much useless dialogue. It takes forever to get to the actual gameplay and most of what the characters say is just natter that doesn't help character development or plot, not to mention the eardrum-shattering noise of the fast-forward function.
There's also a problem with the game itself: you have no choice but to wait until only two people are left in the elevator before you can do anything, which is frustrating because by then, most people would know who the killer is. You have to sit and wait for the dialogue to ramble on, and it's boring as hell.
Also: where did the main character's arm go? Most people who have a limb ripped off and don't do anything to stop the bleeding... they usually die. In fact, the first time I played it, I tried to commit suicide because only a supernatural entity wouldn't care about losing its host's limb and would know how to disintegrate or eat it or something.
So, all in all, good idea, poor execution.