Revealing mistake: When the Lawyer plays the videoclip on the laptop, the stop button is pressed down all the time, instead of the play button. (00:14:40)
Suggested correction: Cyrus was an occultist, it is presumed that this video was haunted. That can also explain why he answers what they key is for in the video after someone asks what it's for.
Revealing mistake: When Arthur hits Cyrus at the end, Cyrus flies back and hits the floor. The floor is meant to be solid and sturdy, yet clealy wobbles when Cyrus hits. (01:18:35)