Slider in homepage (in modal)

Dear weblizar,
Thank you for the nice plugin.
I’ve tryed to use it in a modal on a static page and I’ve already modified the source file as you suggested here, but still I have some problems visualizing the images in the slider correctly.
The site is this one: https://adapeiretti.altervista.org
If you click on any of the “Projects” you will immediatly see what I mean.

Have you any idea why this behavior is happening?

https://www.ads-software.com/plugins/ultimate-responsive-image-slider/