Thanks for your post. It's great to have you involved in the Community
In order to register your Mac just go to anywhere.virginmedia.com
Log in using your Primary My VM details. Go to On Now and select Channel 4 then Watch Now.
Once here an error will come up advising you need to register your device. Follow the prompts to do this and the Mac will then be registered.
Go back to On Now and choose a channel you would like to Live Stream from. This link will also help you: http://help.virginmedia.com/system/viewArticle.jsp?uuid=F9A0DF27-BA3A-4F5D-9C40-FB0B782DAAD2
If you have any issues, let us know and we'll be happy to help.
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