Thanks for an advise about Sigil.
...Ok, I see now. For some reason Calibre not added to the final converted file images from the /img catalog. I did it manually in Sigil. I am talking about converting a few html files with crosslinks(like a web-site sructure with images folder) into a single fb2 or epub-file.
... But when open again in Calibre epub file edited in Sigil images still don't show. Maybe there are some restrictions for the size and type of jpeg images used in epub?
) ... Ok, I think that much more easier just to use some html viewer or browser.