Smooth Slider 2.3.2 is having widget feature. So now you can get the Smooth Slider with your posts in Sidebar without writing any piece of code. You just have to add “Simple Smooth Slider” widget in your theme from “Appearance ==> Widget” section on WordPress Dashboard.
I hope you theme is having Sidebar Widget feature as well.
Let us know in case of any issue. We can discuss the issue on Smooth Slider forum as well,