I wanted to get back with you to clarify the things you need to do to make your Radio and TV active online. Its very simple and I am including a video to show you. All you have to do is load video or audio files into your account. You will upload to the media section while logged into your account dashboard. Once the files are uploaded you will need to create a playlist and assign the playlist to your channel.
Here is a video to show you how to upload: http://www.revmediatv.com/video/17485
Before you can upload files you will need to make sure your audio is in the MP3 format. You can do this on any computer by using free software that rips CD or DVD to convert the audio to MP3.
Here are some YouTube videos that may help. I know that you mentioned you have a Mac so I included tutorials for that Mac. They may give you some understanding:
If you can upload the files in RevMedia TV then I will login and help you the rest of the way.