Almost works

Not able to support what I want to do. I want to show my text, scrolling with a total elapsed time of three minutes. I cant figure out how to make that happen, and i dont have more time to waste on it. There is an uncalibrated speed control that almost doeas what I want. It would be nice to be able to give a number to the speed so that I could make it scroll in three minutes. I tried adding timeline markers, but the feature did not work for me.

YetAnotherNicknameAndPasswordA about Teleprompter