I am having the same problem as a previous writer. The thumb does not pull up the large image.
I recently purchased a licence.
This only started after December 26 - up until that time I have used Highslide numerous times and it has worked fine. It is a wonder program. I am not sure what I have started doing differently.
I use the online editor. A sample page is below.http://ptonline.ca/highslide-custom-example.htm
Thank you for your help.