Looking back over the better quality videos, it does appear that yes, there are "Exorcist style" black walls, as in "black walls but there are scares in them."
The main stretches are going into the maze, "All work no Play" to Grady twins, Elevator to "Here's Johnny," "Here's Johnny" to Lobby, and in the middle of the hedge maze (This one actually has three separate scares). These are very short bits, mind, and in many videos they're hard to even notice.
Some sections actually appear to have scenic in them (The Redrum door shows up in one section, what looks like a projection shows up at the part between the Elevator and Here's Johnny, etc.)
So on the one hand, black walls, but on the other hand, at least stuff happens in them...
Edit: Same thing (Exorcist style black halls) happens in Insidious (Further?) and in ToT during transition scenes and BoH in one of the rooms.
Edit Edit: BTW Awkward Arsic over on Youtube has excellent footage from last night. Link here:
Awkward Arsic - YouTube
Edit Edit Edit: Neither Eligos 'nor the puppet seem to be in AvED. I'm leaning more and more towards the "This was originally an Evil Dead 2 house" explanation.