Thanks
xxueyi for the hint with pdf -> lrf converter, I downloaded it and I will try it, but it is not ultimate solution
Firstly one conversion more ( most of books I have in txt/rtf/doc), secondly I really doubt that that quality will be as good as txt -> lrf conversion. I only want lrf because of quality not because I prefer three letters "lrf" above "pdf" ;-) But I will see.
Anyway I want direct solution not workaround at the end.
Jabberwock, I've tried already to play with styles ("Make eBooks/Sony Reader/styles/external fonts), and I've tried once again a moment ago, still nothing. I embedded Arial, Arial CE, Times New Roman, Times New Roman CE etc. Which font is correct for polish users? If none from default set, how to load a new correct one (maybe a link to them)? I have a possibility only to chose between a few fonts inside Book Designer. In Book Designer also is an option Configuration/Fonts but it has no impact on possible choices in conversion...