Automated Scrolling Panel

Hello. I am trying to create an automatic scrolling panel for a long list of names (text box about ~2,000 px long). I am using the adding a straight motion path technique described in this video: 

https://www.youtube.com/watch?v=xodYSYvq4hQ

However, I keep running into this same issue. No matter how long or short I adjust the motion path line or, how long or short I set the duration, or how long I increase the timeline, the automated scrolling stops at the same point in the list - around halfway down the list. So the scrolling never makes it to the end of the list.

Any ideas how I can get the scrolling to continue to the bottom of the list or at least continue scrolling until the timeline ends? Any other techniques to consider trying?

Thanks.

Thomas