In the right you will see your Store ID. You should copy it.
Go to the Smart Slider's backend Settings → Ecwid generator, paste your store's ID here, and save on it.
That's it, the necessary settings are done, you can create a new slider, or use an existing one.
Choose to give dynamic slides to your slider.
Pick Ecwid - Products.
Set up your generator, choose a category, change the number of slides to how many do you want to be in your slider, change the cache expiration to the time you want your slider to look for new data, and if you want to, you can check, what will be on your slides in the record viewer.
Now you can start working on how your slides will look with the datas of the first slide. You can put down layers, and use the VARIABLE signs to put that data inside them, what you want there to be.