unusable for me

I tried to add another language (German) to my existing Website (English). So I started with “Add new language German”. I followe the dokumentation, translated the strings into German and voila: My original English site was gone, and inside the German, the English content came. Soon after, the English site was gone as well. Maybe I am just to dumb, but after I fiddeled around for over an hour, I decided to let the developers know, what crap they programmed.
So it may work somehow, but if you are unsure what you are doing, keep your fingers off polylang if you don’t want to risk that all your previous work is ruined!