This is easy to do.

1. Copy the video to your flash card.
2. Insert the flash card into your Brightsign and power it up.
3. HD600 or HD2000 users also need to copy an autoplay file (autorun.bas) to the flash card, and name the video autoplay.mpg or autoplay.vob.

Note: This will not play the video in a seamless loop. To seamlessly loop your video (with no audio), you'll need either a custom script, or an interactive playlist that's set to play just one file.