If you don't, you can add one by selecting Add at the bottom of the panel. The audio files are in MP3 format and require a plug-in that interprets MP3 for your browser. If you have Internet Explorer, use the default plug-in that comes with your browser. If it has not been installed, you will be prompted to install one when you call up a presentation. At the prompt, select OK, and the plug-in will install itself.
Icons only appear when the selection is available.
In this case, the product is not available for free trial. Dial the telephone number in the Demo Center for further information. You probably exited the presentation before it ended. To return to the beginning within the slide player, select slide No. 1 in the slide menu.