Scroll down to the "Documentation" section on the page you linked to. It describes how to add files to a zip file. For binaries, you end up using base64, it seems. For text files, you can transfer them directly as strings. Of course, you will need access to the data files to add them to the zip file, which is quite simple if you, say, extract the mentioned data in an Ajax request, but uphill if you want the user to be able to archive files from their local storage.