“I know how to change the slider image in InSync, but the term, “slider” begs the question, can you add more than one image?”
Yes you can definitely add more than one image since that’s the purpose of the Slider (slide through multiple images). If I’m misunderstanding your question let me know.
The Slider area is simply a widget area just like the other widget locations. So you can add any type of content you want inside of it.
Which slider are you using? Are you using the Genesis Responsive Slider? If so, there are some tutorials out there that show how to set it up. Here are some video tutorials you can check out – https://www.youtube.com/results?q=genesis+responsive+slider
Let me know if that helps, or correct me if I misunderstood your question.