First, I think you are confusing me and others by "redefining" what we call these windows:
Singers Display (SD) shows the lyrics highlighting while the song plays. This is a resizeable, scalable window that you can adjust in the second display. It disappears when the song finishes.
Singer Names Display (SND) shows the upcoming singers and their songs if enabled. This too is a resizeable,scaleable window that you can adjust in the second display. It REMAINS displayed when the song finishes playing.
You can resize both displays to be visible at the same time, or make the SND larger and hidden behind the SD, appearing between songs... your choice.
When in question... read the manual. It has details including images to do what you want to do.
