In the newest version of the slideshow the stylesheet has been moved to a separate file, instead of being included on the page. This has been done so the slideshow displays in completely valid HTML. However, if this file isn't included correctly, the slideshow won't be styled. This is the case with your website.
Somehow your WordPress installation removes the URL data necessary in the include of the stylesheet file. This is possibly done by a plugin that removes version data from the WordPress installation or a plugin that has the purpose of speeding up the website.
I'll create a solution to your problem in version 2.2.11, which I'll release either tomorrow or some time next week.
If you find out what's causing this issue to happen, or you have an idea about what could be causing it, could you please notify me?