Venera theme- and slider…

i’m using vs. 2.91, with a very simple template called Venera that is fabulous. i’m not understanding why i can’t get the slider to work?

here is my website link: http://www.xtreme-truck.com/auto-accessories-pensacola

i have followed the instructions for 2.91. i have at least 2 images, i have set my featured category in the theme options, i have used the “set thumbnail” option…but there is just a blank box there.

the instructions say:

Last 5 posts form the selected categoey will be listed as featured in homepage.
The selected category should contain at last 2 posts with images.

How to add images to your featured posts slideshow?
» If you are using WordPress version 2.9 and above: Just set “Post Thumbnail” when adding new post for the posts in selected category above.
» If you are using WordPress version under 2.9 you have to add custom fields in each post on the category you set as featured category. The custom field should be named “featured” and it’s value should be full image URL. Click here for a screenshot.

In both situation, the image sizes should be: Width: 610 px. Height: 320 px.