PHP code to import a slider
You could create your own sample slider importing page in your theme/template. You could simply create your sliders, export them and put all those ss3 files somewhere into your website's ftp. Then the php code you can use to import these sliders is this:
$sliderID = SmartSlider3::import(get_template_directory()."/samplesliders/home-slider-1.ss3");
The import function of the SmartSlider3 class will import the selected ss3 slider into our backend, and it will return the ID of the slider to you, what you could use for example to publish this slider right away after this importing action.