The best method is entering note-based lyrics in the Notation Window and these would show up in the Big Lyrics Window.

If you don't want to enter note-based lyrics in the notation window, there's also the ability to add Section Text by right clicking in the notation window - Insert Section Text which would let you enter Section Text that would show up on the notation window. (but not the Big Lyrics Window)

Another different method would be to use the Markers button on the Markers section of the RealBand toolbar that lets you add Markers (another type of text-based event) which will also show up in the Notation Window as well as the Tracks Window. (but not the Big Lyrics Window)

Using the Comments Window would be the easiest method but it won't scroll automatically during playback.

Jeff Yankauer