Ok, I'll do some tests then and see how it goes
Ofc I'll keep original files just in case.
Also what bothers me, and maybe you know how to fix it.
When I open new book then it always set publisher font, ignoring my Kindle settings and I have to change it manualy and then its fine. But I guess it shouldnt work this way
Edit:
I found this thread on reddit
https://www.reddit.com/r/kindle/comm...or_sideloaded/
With same problem, but noone replied there :/
Edit2:
Updated to 5.17.1.0.3 and it seems to be fixed