Using Roll20 to Project Maps Through a TV

I have a digital tabletop using a flat screen TV and Roll20 as the software to project. (Check out my video on the table I made to use the TV.) This video shows how I prepare and upload the maps for D&D. Here's the link to Roll20: https://roll20.net/ The free Ravenloft maps I downloaded are from: http://www.cartographersguild.com/showthread.php?t=13943