Modify a plugin - Make it compatible with current version of Woocommerce

In a Wordpress website with installed Woocommerce, I was using a plugin (Auto Category Image) that is basically a code that does the following: If a category or a subcategory has no image then it uses either a random or the latest product image that belongs of that subcategory to shows it as a category image. I found it on the web and it called auto category thumbnail. I found it also as a code that you can add it in your site. That plugin was working until previous version of wordpress and woocommerce but now is not working any more. My version now is: Version of wordpress 4.7.5 Version of woocommerce 3.0.7 Theme: E-Shop In the attached file you can find the plugin code and also some screenshots of the plugin options page. The website is [login to view URL] I need a skilled coder to modify the plugin code to make it work with the current version of Woocommerce and Wordpress or use any other way to automatically set the product image of one random product of that category, as the category image.