There is no tutorial.
To add a background image for one of the tabs:
1. Place the widget
2. Click the button to open the basic options
3. Enter the image URL in the correct "Background for Slide #x" text box for the tab you want the image on.
To add content for a tab, place a different widget in the corresponding "Horizontal Accordion - Slide #x" position.
The closest thing to a tutorial is the Shaper, which is a full WP install, with all demo content and extensions included.
what you just guide above is when i use the widget as standalone, but I am using zoka theme, and it's already a widget position of horizontal accordion. I was installing using the shaper, and there is no image on the horizontal accordion. Maybe you can take a look
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