I explored this area in the 1990s, with my uncle. We were mainly interested in the lines which became the CNE. We spent a considerable amount of time on the lines around Pine Plains. Over the summer, we covered everything between Hartford, and Campbell Hall. We did the Springfield Branch, including the detour around the Montague farm.
On a side note, I have been researching my family history. One family member started his railroad career on the D&C, predecessor of the ND&C. He started on the survey crew, and later became a civil engineer. Eventually he was Norfolk and Western's chief engineer.