Sorry to hear about this and we are here to help. I see that you stated that you have a Windows 7 computer and are using a 64 bit browser. With that being said what we will have to do is use a 32 bit browser, unfornately we do not support the 64 bit at this time. You will have to download the 32 bit if you do not have one on your computer at this time. Usually in the start menu and under programs you will see two IE one says 64 and the other wont say anything after it. This is the one that we will want to use. If you have any questions please dont hesitate to reach out! Also here is a link that I hope will be helpful as well.
Hope this helps,
Sling Moderation Team
Shawn - I did see this article, but the way it's framed, they make it seem as though the deciding factor here is the 32/64 bit browser as opposed to the OS. I have used IE and FF both in 32 bit mode (as denoted by the *32 in the process monitor). Can you confirm if this is just tied to the broweser or does the online sling player not work for any version of 64 bit windows? Since I am using a 32 bit browser (2, actually) I would not anticipate running into this issue.