It is not here about SP language (why asking ? It's in the FAQ) but about (excellent) spelling.
One part of my original question should be as follows: when should we "translate in English" places names and when not.
The question might sound absurd, but in some languages (slavic between others) we declinate surnames (then place names), something unimaginable in other languages where surnames are sacred and unmodifiable (tennis player Caroline Wozniacki, not Wozniacka, is an example).
Which perhaps explains the tendancy some countries to systematically translate all places names that can be translated. Making unclear the barrier between what one would call "etymology of a place name" and "excellent English".
One example: should Hajducka vrata be Rebel's door ?