This code allows you to change the background image as you'd like to show a change in scene. Look for background-image in the code and replace the link with the URL of your desired image. Suddenly switching backgrounds might look a bit jarring though, so maybe you can try adding a fade transition. The next slide goes over how to do that.
Look! No name box! It's very easy to add/ remove in the code as you'd like. To remove the name box, in the code, look for the line that has "--NAME BOX-->" and remove the > from that specific line of code. If you want to add the name box again, just add the > that you previously removed. And another thing!
By the way, the first slide always starts at number 0, so even though this screen is numbered 19 in the code, it would technically be 20. The first slide (i.e. 0) is the title screen though, so you don't have to worry about this. It's just something worth noting. The next part is important to note though.