Odd fix for Dragon Age 2 Direct X 11 LaunchError on Steam.
A little background on my rig... in case it's an issue
Alienware M17x
Intel Core I7 CPU Q740 @ 1.75 GHZ
8GB RAM
Dual NVidia GeForce GTX 285M w/ updated version 331.82 driver
128GB Solid State Drive
Windows 7 64bit Home Premium w/ Service Pack 1
So I tried running Dragon Age 2 on Steam utilitizing Direct X 11 through the DA2 Launcher's configuration. Every time it crashed with the "Dragon Age has stopping running... etc."
I validated the local files on Steam, removed all mods, removed all DLC, removed Hi Res Texture upgrade, reinstalled Dragon Age... scratched my head and just about gave up. Then I figured 'what the heck' and ran it on Direct X 9. Amazingly it worked. However, when I went to the video settings under Options, the Graphics Detail could only be set to Medium... so in a fit of rage I hit the Reset to Defaults... and something strange happened.
Suddenly, I could set the Graphics Detail to high. (but still not Very High) So I reloaded all my mods, Hi Res Texture Pack and went back to options maxing everything out. I then exited Options but second-guessed myself about a certain setting and went back into the Video menu... My Direct X option was now set to Direct X 11. Upon exiting the game I went back to the Launcher Configuration and sure enough, it was set to Direct X 11. Now, the game crashed when I tried to load it, so I repeated the my earlier process of using Direct X 9, Reset to Defaults, then maxing everything out... and the game went back to Direct X 11 upon leaving the Video Options.
Hopefully if there is anyone else with a similar issue who has not reached the same conclusion, you can use mine.