In most of the cases where we have seen something like this before it has been caused by the web server configuration not passing the extra information after index.php.
What web server are you using? Is PHP a module in that web server, or are you using some sort of CGI setup? Does the web server have permissions *all the way* from the root to the book?
You mention Windows path names: does the case of the letters match? There can be no end of trouble moving windows libraries to linux, because windows is very happy to use "author" while the folder is named "Author". Linux doesn't like this at all.
I also note that the title in the URL does not match the title in the file system. The link is missing the "Author -" in front of "Some Book Title". This is strange, because it indicates that the info in metadata.db does not match the info in the file system.