Can you look open a command prompt, and then run the following:
cd /d "%PROGRAMDATA%\Microsoft\ehome\package\MCEClientUX"
dir /s markup.dll
You should see at least one file, and it should be ~3.6 megabytes. If you don't see that file, then you aren't downloading packages. If you do see that file, then I think there's something wrong with the firewall. Can you try disabling it and seeing if the tiles show up again?
Thanks,
Jeff
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