When I first published Buddy, here's what I did:
I copied and pasted the whole thing from OpenOffice to Microsoft Word. Then I made whatever adjustments I need to make. This included things like hyperlinks and page breaks. When I had it the way I wanted it, I uploaded that .doc to Amazon.
And then I used the "preview" function to check it out. To my surprise and dismay, the last paragraph was in a different font from the rest of the story. So I went into Word again, highlighted the problem section, selected the proper font, saved, and re-uploaded the file.
I eventually got it fixed, but it took a few tries. It drove me nuts. I basically had to backspace the whole last part of the story and then re-type it.
The problem, as I later discovered, is that Microsoft Word likes to insert a lot of "junk html" into the file, and that stuff doesn't play well with Amazon's file converter. So, for Mr. Wilson, I decided on a different tactic.
OpenOffice allows you to save your file as a .doc if you want, so I figured I'd do that. That way, I wouldn't have to open Microsoft Word at all.
And it worked. Flawless conversion.
So, for novice users of KDP, my recommendation is to write in OpenOffice. The program is a free download, so there's no reason not to at least have it on your computer. Then, when your file is ready for uploading, save it as a .doc file. Then upload that .doc. DO NOT use Microsoft Word to make any changes to the file.
This will save you some headaches. Trust me.