Hello Anthony,

Thank you for getting in touch with us!

I checked the attached video. You can achieve this layout without thumbnails too, if you use static layers.
Maybe it is easier to configure and customize them. For example you should check these slider from our template store which has static layers for navigation:
https://layerslider.kreaturamedia.com/sliders/creative-portraits/
https://layerslider.kreaturamedia.com/sliders/furniture-slider/

Wordpress doesn't allow upload SVG's by default, but if you have a plugin for that then it should work with LayerSlider.

I think the problem is that you use a fullsize layout with the 'fit to parent height' mode, which takes on the height of the parent. Which is not given a height because it is an auto expanding element. So either add a height to the contents of the tab or choose another layout mode. Is the start in viewport option is enabled in the slider settings / slideshow tab? This can be a problem if the slider on your page cannot scroll to the center of the screen because the slider is at the bottom of the page.