Hello, Stefano!
I did try to send you the file through email, but your server rejected it. Here is what I wrote. Instead of sending you the file, I’ve inserted links.
I have found several sliders that totally knock out your plugin once installed. Here are two… I’ll send you the zip file for SliderVilla’s
Testimonials Widget by Axelerant – https://wordpress.org/plugins/testimonials-widget/
Testimonial Slider by SliderVilla – https://wordpress.org/plugins/testimonial-slider/
I am not suggesting that this is a problem on your plugin, but there does seem to be an issue with several of the testimonial slider plugins.
Thank you,
Heidi Hafner
Hafner Designs