Slider control

Hi All

I am trying to have a slider increase the height of a shape in Storyline 2. Similar to the cause and effect example on this video tutorial. https://community.articulate.com/series/getting-started-with-articulate-storyline-2/articles/working-with-sliders

 Anybody any idea? I assume it uses JavaScript to get it that smooth - or do I need to create multi-state object and animate using multiple variables to trigger the change?

Any help greatly appreciated.

Thanks

Andy