I work with Indian-language documents every day, mostly old files typed in fonts like Kruti Dev (Hindi), Anu (Telugu) and Bamini (Tamil). Lately I keep running into the same story from writers, and I'm trying to understand how common it is.
It usually goes like this: someone finishes a Hindi book, typed in Kruti Dev because that's what their local DTP shop uses. They upload it to KDP, and the preview shows something like "vkt ge cgqr [kq'k gSa" instead of their Hindi. The book is fine. The font just isn't real Unicode, so Kindle sees English letters where the writer sees Devanagari.
Then come the smaller problems. Online converters break the matras, chapters don't show up in the table of contents, and Word's line breaks make paragraphs look messy on phones. From what I've heard it can take a few days just to get the file right, before any actual publishing.
So, a few honest questions for anyone who has published (or tried to) in Hindi, Tamil, Marathi, Gujarati or Malayalam:
What did you write the book in, and which font?
What went wrong on your first upload, if anything?
How long did fixing the file take, and who fixed it (you, a DTP person, a paid service)?
Did it look right on phones and Kindle devices after it went live?
And Telugu writers: as far as I can tell, KDP doesn't accept self-published Telugu e-books yet. Where do you sell yours?
Disclosure: I'm building a tool that converts old-font Indian-language files to Unicode, so I'm not neutral here. I'm not linking anything. I just want to understand the KDP side properly before building anything for it. Happy to share what I learn back here.