Since this specific update was one of the last stable patches for CS6, make sure your GPU drivers are current. CS6 relies heavily on the "Mercury" engine, and if your graphics card isn't recognized, you'll lose out on those fast 3D features and smooth zooming.
Adobe Photoshop CS6 Extended: Why Version 13.0.1.1 Still Matters Adobe Photoshop CS6 Extended 13.0.1.1 Multilang...
To run Photoshop CS6 Extended 13.0.1.1 Multilang, your computer should meet the following system requirements: Since this specific update was one of the