Posts do not open with Flexible Posts Widget

Flexible Posts Widget gives me the great opportunity to build a website with news in columns per category. I placed three widget areas for three categories on my homepage. The page looks good, but if I click on the titel of a post nothing happens. The right url appears in the url bar, but on my screen the pages stays as it is. It is impossible to see the content of the post. What do I do wrong? By the way: I build my theme with Headway Theme Builder.

https://ww.wp.xz.cn/plugins/flexible-posts-widget/