OK,
Got Epub download through HTML working with a database directory stored outside the web path. Solved it by changing the last line in fetch.php according to
this comment.
Minor issues that do not obstruct the main purpose of COPS:
* Cover preview in fancybox does not work. Probably related with the fetch.php thing as mentioned above
* Title summary in fancybox --> Fancybox starts halfway of my Ebook screen. Re-positioning necessary