I think
it is time to sum up the topic:
First - thanks all for the tips/hints/advice. It helped a lot and led to a solution.
The
best method to convert Google Doc to EPUB I found is:
- Download Google Document as .epub
- Open it in calibre and click "Convert book" button + Save
- Open in Sigil and Find/Change remove "page-break: avoid" tags from css.
- Make some other Find/Change operations if needed ("Saved Searches" function may be very useful here).
This method is quick, easy and produces fine results with relatively nice code.
THANKS TO ALL FOR HELP AND COOPERATION.