I was having a lot of trouble as well. I found this forum and tried everything that was suggested and still nothing worked. So I figured if I downloaded the latest version of the theme then maybe some new option would pop up under pages or posts templates. Still nothing.
Then I tried opening up the readme.html file that downloaded with the updated theme. There I found my answer and fixed the problems, and there were quite a few. Here it is membership FREE: https://alienwp.com/documentation/oxygen-theme-documentation/
Read the instructions carefully and I guarantee the slider will start working for you! Its a beautiful feature once its set up. My site is still under construction, but I’ll be sure to post it up once it’s complete
Wishing you the best!
