If you write in Word, you should understand/accept that Microscoff adds tons of proprietary coding. You can see it if you view the document in html code. Very messy and I'm not good enough with html to know how to clean it up.
So I updated that Her Cold Kiss book, gave it a new cover, a little bit of a new ending so that it ended and was no longer the 1st book in a series. I added a Table of Contents. Okay. Uploaded it to Amazon. Fine. Lovely.
If it looks good on the Kindle Fire, I figure I'm set.
I upload it to Kobo. Total and complete corruption. Pages with 1 sentence. Really bad. Not just the indent is off. Uploaded it to BN. Same thing.
For the next week, all I did was strip and reformat this book. Generally any small problems can be handled in Word itself. There's an eraser icon (whatever it is) and you click that and it's supposed to put you back to square 1. Not always, or not completely. What you then try is to save the document in rtf, open it in wordpad, save, open it in Word and all the formatting is stripped.
Not this time. I did that several times. I opened it in Open Office, saved, whatever. Nothing worked. I unpublished it from BN. That happened immediately. I tried at Kobo, it got stuck. Apparently Kobo support doesn't work on the weekends. Good to know. They finally deleted it yesterday. Meanwhile an adequate version made it through BN.
I don't quite understand why this has to be so difficult to the point where the average person can't do it.
I also have some confusion about the TOC/NCX file. Amazon is beginning to nicely push publishers to include a TOC. Fine. We covered that here some months back. Then this NCX file issue came up. It's hidden, it stands for Navigational Control for XML. It's what gets you around. I started to hear about creating this blasted thing and all this stuff I couldn't understand. I'm a writer not a coder!
If you download the free program Sigil and look at your document that you wrote in Word and created the TOC in Word, and then save as a html, filtered file, you can look at what's in your document. You'll see the NCX file.
You don't have to build it, or do anything. Word has done it for you. So relax, that's one less thing you have to worry about. But you are going to want to put TOCs in all your books and start going back into your old ones and do them, too. Sorry.
You can do it in Sigil if you don't want to do it in Word. It's even easier there. Or you can pay someone to do it.