Diagnostics would only be useful if you had the mod installed properly to start with.
It sounds as though you have the SQL installed corrected, but your files are missing or misplaced.
If they were correctly located
this link to your site would show the hover stylesheet, but at the time of writing gives a 404 Not Found Error. Similarly for
this link to the main javascript file, and the absence of any hover box additions to the HTML generated for your product information page, suggests that the normal Zen Cart file is still being used to insert the main product image, i.e. no hover box file installed for that either.
As the path to the javascript files doesn't require any editing, this is not a case of getting misspelling the template directory name.
To get to the bottom of this, could you tell us the full pathname to the location where you have placed the new tpl_modules_main_products_image.php, stylesheet_icimghover.css and jscript_icmain.js files?