Plugin doesn't work with my template

I have a wordpress template that is horizontal scrolling, but each page has a different height, depending on the content. I have made a custom widget area above the page content for sub navigation that uses anchor tags. For some reason the plugin doesn’t work with my theme. I checked off Fixed Widget, changed the margin top and screen max size and still nothing. Any help would be most appreciated.

-S

https://www.ads-software.com/plugins/q2w3-fixed-widget/