Hi @davidvm, there has been no changes yet for the random slideshow feature, this is still not built in to the Slider. I cannot give you an exact ETA on this. When there is an update, we will update our page:Design Responsive Websites - Webflow.
We do not support editing the webflow.js at the moment. I can reach out to our team and see if they have any ideas for you on this 
Cheers, Dave