Hi silvertop,
I've had a read through the instruction book about the Lyric Document Window and my impression is that it isn't misleading. The information seems to simply state what LDW is and does but doesn't go into too much detail on how to get the best out of it.
Here's something you might like to try that will give lyrics and chords in the Big Lyric Window....
... it's not necessary to enter every song note for note-based lyrics. Simply go to the Notation Window and place a note on beat 3 in each bar. Don't worry about the pitch of the note. It's then possible to use this note to anchor lyrics for that bar. I call these "bar-based lyrics". The reason I use a note on beat 3 is because lyrics are centre justified and beat 3 will fill the bar from the centre outwards. Below shows what I mean.

Once the lyrics are entered, it's possible to delete the note and the lyrics will remain. (Muting the melody would also stop the notes from sounding if you want to leave them in place. I favour leaving the notes in place because it makes editing the text easier, if needed.)
Hope this helps,
Noel