Onsong - Lyric Scrolling

My goal in setting up page scrolling in OnSong to show lyrics is to do as little as possible with the foot pedal. I need to use other pedals, so I need OnSong to be as feet off as possible.
 
To display the song while I perform, I make sure the song is laid out linearly. In other words, all the words are included on the page, including duplicate content like choruses.
Now I use the duration to control how long it takes for the song to scroll. In theory, all I need to do is start scrolling and play along until the song scrolls to the bottom. 
When I use my BeatBuddy, it keeps my tempo, so I play the song the same every time; this works out perfectly when I use the BeatBuddy.
Without the BeatBuddy, the timing works fine when Im practicing; however, when I get in front of people, I usually play the song a little faster than I should.
Because of this, I need to use a foot pedal to help control the scrolling. I use a two-button blue tooth pedal to accomplish this. I set one button to start/stop the scrolling and the other button to do a page down.
If I play too fast, I can stop scrolling for a bit and then start back up again.
I can use the other button page down if I need more words to show.