Need help with FXAA

[=FI=Murph]

Yes. The easiest thing to do is disable everything except AA in the injFXsettings file, which should have been included in the download. Open it with notepad and change the following settings;
SELECTION
------------------------------------------------------------------------------*/
// Comment to deactivate an effect.
// Example: To disable the tonemap effect, use // in front of #define USE_TONEMAP
#define USE_ANTI_ALIASING
//#define USE_PRE_SHARPEN
//#define USE_BLOOM *NOT WORKING
//#define USE_TECHNICOLOR
//#define USE_TONEMAP
//#define USE_SEPIA
//#define USE_VIGNETTE
//#define USE_POST_SHARPEN
//#define USE_FINAL_LIMITER


/*------------------------------------------------------------------------------
FXAA SHADER
------------------------------------------------------------------------------*/
// Set values to calculate the amount of Anti Aliasing applied
float fxaaQualitySubpix = 2.0; // Default: 0.75 Raise to increase amount of blur
float fxaaQualityEdgeThreshold = 0.01336; // Lower the value for more smoothing
float fxaaQualityEdgeThresholdMin = 0.01336; // Lower the value for more smoothing
This should prevent the program from affecting anything except FSAA.