Some of you may be aware that Kieran Foster, a student at De Montford University, has been writing a thesis on unfilmed Hammer. I've been eagerly awaiting the results of his studies so imagine my delight when I discovered that his thesis has been published online and is available to download here: https://www.dora.dmu.ac.uk/handle/2086/18247
I haven't read any of it yet but a quick skim suggests that it's going to be extremely interesting, if by no means comprehensive as it seems to be based entirely on the material currently deposited in the Hammer Script Archive. Enjoy!
Thanks, Mal. I'll certainly take a look.