Bear in mind that you cannot execute a package that has been published for web distribution just by opening the index file in the browser. You must open the zip file on your web server or intranet for it to run properly.
To run faster tests, we recommend that you publish your course as a link so that you can easily visualize it on your browser by copy-pasting the link.
Anyway, you may take a look at this article from our Help Center where we explain all the ways in which you can visualize a course in your computer.