You image can become blurred if the shutter speed is to slow. For example, if your camera says that the proper exposure would be f / 5.6 @ 1/30 of a second, then you would be able to increase your shutter speed to 1/125 of a second @ f /2.8. The rule of thumb to follow is: take the reciprocal of the focal length being used.
On computers running Windows 8.1, if CameraWindow does not start up when a camera is connected, please confirm that Microsoft .NET Framework 3.5 (hereafter referred to as .NET Framework 3.5) has been installed.