Platform 15.0.2 (May 17, 2018). Please donate.
400+ real apps, New: Falkon browser (Jun 04, 2018)
Over 980 million app downloads
OpenOffice is already localizated into Czech see:http://www.openoffice.org/download/other.html#aoo
Would it possible to have portable OO also in Czech?
Grab yourself a copy of LibreOffice Portable. It's OpenOffice but with even more features. Created by most of the old OpenOffice development team that left when Oracle messed up the project.
Sometimes, the impossible can become possible, if you're awesome!