This does not do anything useful

I am sorry to say this but the utility level of this plugin in my scale is about 3-4 (out of 10). The purpose of this plugin is simply to create a book post type, which will give you a short code for each of the books, so that when using it in a page or post you will see the book image and a buy button, which links to the book at Amazon (or other stores that you put in).

You could simply create a page with the image/s of your book/s and add a “buy at amazon” link next to them.

The css also seems to conflict with bootstrap “code” selector, overwriting its rules.