PDF and ZIP files are shown automatically in the Access Statistics > Files report. It is also possible to get detailed information on individual files by adding file names or wildcards (e.g. *.zip) in Profile Properties > Tracking.
If no information on these files is shown, you should check that the files are stored on your servers, and you not link to files on other servers the program don't have data on.
If no information on these files is shown, you should check that the files are stored on your servers, and you not link to files on other servers the program don't have data on.