This Quicktime message popup can be used for audio or video. You can use .mp3, .wav, .mov, .avi, .qt or any other QT standard web supported audio or video files. Resize the video player by editing the player-quicktime.js.
Edit the welcome-quicktime.htm in the message folder to update this page. Edit the text sizes and colors on this page by editing the corporatestyle.css. The image on this page is a standard .jpg image you can replace.