Ollie,

          Glad it worked for you and you're happy with the result.  I'm sure a document of that size took several hours to process.  I think the largest I've ever done is a bit over 400 pages, and most are significantly smaller than that.  When you get into large PDF files, even OCR-ed ones, you pretty much have to be able to word search them to make finding that "needle in a haystack" a reasonable task.

          I still can't explain why CTRL+SHIFT+C is not working for you without using pass-through as it works just fine for me when I'm using NVDA 2016.1 and PDF-XChange Viewer together to do an OCR that way.

          I have suggested that others contact Tracker regarding accessibility issues.  While I can and do use screen readers as part of testing things out, and can say what works or doesn't work for "routine stuff," there's nothing like a skilled screen reader user who has to do "the deep stuff" to uncover, and even to explain, accessibility issues I will never encounter.

Brian