You forgot to add a small opening for food delivery and handcuffing.
Yes I did. I’m using Substance Painter and Blender appears to be very finnicky about exporting anything but the simplest meshes to FBX format. No one has helped me to resolve that problem so I must work with simple meshes for now.
Ok, that makes sense. But why FBX? As far as I know (from googling) Substance Painter also supports dae, which is default file format for Blender.
I didn’t know that. I got the idea somewhere that I was supposed to use FBX.
Unfortunately, I’m now having problems with SP loading the dae file.
So it’s basically like jumping from a kettle to a frying pan. You have wider horizon, but you are still in trouble 
Nice! Have you tried to add fog?
I can’t find a tutorial for doing fog in cycles in 2.8.
Just used this over weekend, hope it helps…
And this for more control in the composting editor…
This tutorial won’t work with 2.8. Different set-up.
This tutorial is missing half of the lesson.
These shackles look real nice. The door as well.
Just out a curiosity. Can you actually move with the shackles with something (that they stay connected and collide) or is it “just” mesh. I was always doing it like static mesh, but interested whether you took another approach.