Robin Hardy did a storyboard of the first movie, 280 pages by one account, and is planning on making a graphic novel out of it. He talks about that at the end of the (2012) article below. I’ll research this some more but does anyone know anything more about this? I’m especially interested in any missing scenes. (Ingrid Pitt chasing Howie when he discovers her while searching the houses for one…)
Here's a screencap of an article from Sight&Sound (October, 2013) that shows a few pics.