There is a translation mistake in the Polish version (PC). When selecting a feats, there are two ‘Twardziel’ choices in the list. This is a error, one should be ‘Twardziel’ (‘Durable’ in the english version) and the other should be ‘Krzepki’ (‘Tough’ in the English version). Once the feat is selected, it is already translated well in the character sheet. You probably need to change the key:
<content contentuid="h50b861bdg5897g416fg8310g535d08356712" version="1">Twardziel</content>
to
<content contentuid="h50b861bdg5897g416fg8310g535d08356712" version="1">Krzepki</content>
