[Help Wordpress] Click on the slide should go to an external url

Click on the slide should go to an external url

Hi,
I would like the users to see an external link when they click on some slides.

This post explains how to do it http://help.dimsemenov.com/discussions/royalslider-wordpress/3110-slide-click-brings-up-lightbox
but it does not tell how and where to set {{description}} variable. Where is it?

Can I set the variable {{link_url}} somehow?

Thank you.

Regards,

.

help.dimsemenov.com