Thanks for reaching out to us here! I do apologize for any inconvenience you're experiencing while trying to view your Slingbox through your WD Live. We are working on a software update to resolve this issue. In the meantime, there are a few things you can try as far as your home router configuration.
Here is an article from our support site with some additional information regarding manual router configuration:
Hope this helps!
The Sling Moderation Team