You were right, I messed something with js scripts. I restored oryginal files and it works fine. Thanks for your effort.
Hi, slider works fine, but I’d like to have thumbnails under the slider, like on the example I posted.
(after following link above, enter any product)
I worked it out. It was something with those ?? symbols in JS script in your screenshot, referring to language (as i checked in console). I have changed wordpress language from pl_PL to en_US and now it works. Thanks for your effort.