Cocksie,
The newspaper articles make very interesting reading. There are obviously a few bad eggs named James Hall in the area. As the James Hall in this case was 'tramping' I do wonder if any of these are him. But still very worthwhile having as some of them may fit in with 'our'

James Hall. There is the possibility that he may have had an alias at some stage.
Your suggestion about trying to find the vaccination records for Mary Ann Fisher is an excellent idea.
So it would be ideal to have a volunteer or two 'on the ground' so to speak, who is willing to do a bit of detective work for prison records and, depending on whether or not the Nottingham Archives gets back to Carol, maybe chasing up Workhouse records too. (I suppose Nottingham Archives are understaffed and overworked like most Archives.

)
It is up to Carol's of course, but as it is fact that James Hall was the man who abused Mary Ann, maybe prison records will give additional details. Perhaps these could be searched while waiting for the certificates? I'm sure if Carol were to put the call out, there would be someone more than happy to help.
Just an idea.

PS, Some excellent links California dreamin.

They look promising. As James was tramping, it is worth doing checks in both counties - Derbyshire too? I can't remember which were mentioned in the last thread