Thank you, Hicks.
I actually had to spend more time on the background. As you know from the film, there is no complete view of the chain room. You might remember in the movie, the camera view starts at the bottom and then pans up to reveal the upper area with water dripping down. I grabbed a number of screenshots from bottom to top, pieced them together, and blended the seams.
Unfortunately, the camera view did not pan up parallel to the view. It did a swivel pan up (sorry, I don't know cinematography lingo/talk). So that changed the angle on objects when piecing it together. The large machine or whatever it is, suspended by chains, blended okay. But it was the chains that are out of whack. In fact if you look right under the creature's right hand, you can see two chains not lined up. Each time I tried to line them up it threw the big machine out of whack. So I sacrificed the chains in favor of the machine.