Very Very Slow Loading

Hi handy little plug in, but I just checked the finished site on all the major browswers, android & Ipad. The gallery Slider is far too slow loading.

Is there anything I can do too speed this up. I cant give this site back to my client with it loading so slow. visitors would just give up.

I dont see how the images files can be too big & I only have 12 images loaded into the gallery

Thankyou in advance,
Richard

https://ww.wp.xz.cn/plugins/gallery-images/