I am not sure where best to post this. My wife and I are now happily playing without issue on both PC's in my home, but I wanted to pass along the solutions I used for the issues I encountered getting the game going.
*Disclaimer* Some of these suggested steps could cause your PC to stop working if it encounters an error, or you are not sure of what you are doing. I urge you to research each suggested fix online and learn more about it before you attempt it. Most of these items are very simple, but that does not make them totally foolproof.
I own 2 PC's. One i5 and one i7. Both running Windows 8 Pro, 16GB of RAM, and ATI Video. One has a 7770 and the other has a 6870.
I had 2 issues after downloading the launcher.
1) Both PC's would randomly crash to desktop (CTD) when playing the game regardless of graphic settings. I also noted studdering on shadows.
2) The PC with the 6870 got a black screen when I loaded the launcher.
1) The CTD was caused by my ATI Video Drivers. I uninstalled the version I had, rebooted, and installed the latest version form ATI. Smooth sailing since. Both PC's are back to the Desktop High settings or whatever they are called. Game looks beautiful and no studdering or crashing.
2) The black screen on the launcher was a bot more of a pain. Long story short was that I had to reprogram my computer to get it to load. In the process I was able to isolate what I believe to be the cause of the issue, but I was not able to find a less destructive method of resolving the issue for my computer. However, I did learn several possible solutions that may keep others from having to go as far as I did.
The cause...
Internet Explorer. I am not sure how or why, but the launcher pulls settings from IE.
Possible Resolutions... (this should be the general order to troubleshoot in)
* Scan your PC for a virus. As the Launcher seems to rely on IE your issue could be caused by a virus or add-on.
* Try uninstalling the launcher, rebooting, and reinstalling.
* Try Resetting Internet Explorer (Control Panel > Internet Options > Advanced > Reset)
* If you have Windows 7 you can try uninstalling the Internet Explorer 10 Update.
(Not an option with Windows 8 as IE10 comes preloaded. Removing/Adding the feature is not the same as uninstalling/reinstalling FYI)
* Try Uninstalling Microsoft Silverlight. Reboot, and install it again.
* Try System Restore. If you can find a restore point that is far enough back you may get lucky.
Reprogramming is your last resort, and as mentioned above is ultimately the only resolution that worked for me. Once I backed up all of my data and took the plunge I was playing the game within a few hours. I keep a regular backup of my files and was able to get my Starcraft 2, Diablo3, Rift, ect from my Wife's computer to save on download time. I hate that I had to go so far to get it working, but it was worth the effort, and my computer is running better to boot.
Whatever was causing issue with Internet Explorer had also been preventing Netflix form working outside of the "Metro" app. This leads me to believe that it was either Silverlight or an update to IE that damaged my IE to begin with.
I hope that someone finds this post helpful. I hated to just sit on what I had learned when there may be others out there experiencing the same issue.