Thumbnails not working

Hi,

we are using cyclone slider 2 for our magazine http://siehdiewelt.com/goldrausch-den-karpaten/. Great Plugin. But since a few days we experience problems with the sliders (thumbnail template): A click on a thumbnail used to show this image in the big slider, but now nothing happens. I don’t know what is causing the problem, no new plugins have been activated.

Also the plugin-author (codefleet.net) is not responding to my emails, which is really not cool.

Grateful for any help,
Markus

https://wordpress.org/plugins/cyclone-slider-2/