Hi Herman,
PlayIt Live does not have a concept of "playlists". PlayIt Live works with a continuous log that is scheduled into hours. If you add songs to the current hour, and then come back to the software 3 days later, the new current hour will not be the same hour that originally added the tracks. If you plan to use the songs in a future hour, you should scroll to the future point in time, and drag and drop the songs into the future hour.
Herman Morris