HunchBluntley: He seems to be able to read PDFs; I guess maybe one or two other posters are probably correct in guessing that he (somehow) doesn't know what a ZIP file is. :OHunchBluntley: If you're talking about the downloadable extras, they come in compressed form; simply right-click on the .ZIP folder you downloaded, select the option that's called something like "Extract...", and go from there.
But you should know that a lot of GOG games that come with separately-downloadable manuals also put those same manuals in the game folders when you install them -- in many cases, there are even links in your Windows Start menu! :)
EDITED for clarity.

Xambro7: I can't use the rules manuals in DOS format....can't they be made into PDFs?