I have noticed the translation to Swedish of the user interface is completely wrong in some cases. As my native language is Swedish I prefer to have Swedish selected. These translation errors have confused me, making it harder to use LingQ.
For example I tried to add an imported lesson to my playlist. With UI set to English it’s easy to find the function in the lesson options, but not in the Swedish version. The option is there, but with a wrong text, and I didn’t find it.