At scheduled times, as well as manually, we want to be able to overlay a text message that will be delivered simultaneously on all screens, overlayed on whatever is already playing. Is this possible, and if so, can it have a scrolling effect?
For example, we will be holding a sweepstakes, so we want to notify people that "15 minutes until the drawing. Please enter now!" and also, when someone wins, we want to be able to display "Winner: John Smith! Come get your prize!" for a minute, but very subtly blended over the existing video.