Ok. So you need to make sure that all of the files you need have been fully downloaded and they are all in the same location. You then need to use either Winrar or 7Zip to extract them.
This is important. You only need to extract part 1 as all the files are linked and the rest will extract automatically.
If your problem persists it may mean the the files have not downloaded properly, this is not a problem we can send you direct download links for your workshop manual, just let us know.