Hope that works for you, regarding the <h1> tags, what I meant was the original looked like this:
Code:
<h1> Title</h1>
1st paragraph without being surrounded by tags
<p>second paragraph having tags</p>
While it needed to look like this:
Code:
<h1> Title</h1>
<p>1st paragraph surrounded by tags</p>
<p>second paragraph having tags</p>
In general it only took me a couple minutes to look through and repair that file, you just need to search through all instances of the tags I mentioned. Then again that was a relatively short article, a book in that state would require a bit more dedication.