For people who don't know what the archetype config is here...

<VIDEO>
<WIDTH>800</WIDTH>
<HEIGHT>600</HEIGHT>
<COLORBITS>8</COLORBITS>
<GAMMA>255</GAMMA>
<FULLSCREEN>TRUE</FULLSCREEN>
<REFLECTION>false</REFLECTION>
<LIGHTMAP>false</LIGHTMAP>
<DYNAMICLIGHT>false</DYNAMICLIGHT>
<SHADER>false</SHADER>
<CHARACTORTEXTURELEVEL>0</CHARACTORTEXTURELEVEL>
<MAPTEXTURELEVEL>8</MAPTEXTURELEVEL>
<EFFECTLEVEL>0</EFFECTLEVEL>
<TEXTUREFORMAT>8</TEXTUREFORMAT>
<MOVINGPICTURERESOLUTION>1</MOVINGPICTURERESOLUTION>
<MOVINGPICTUREFILSIZE>3</MOVINGPICTUREFILSIZE>
<NHARDWARETNL>false</NHARDWARETNL>
</VIDEO>
How to use:
Note: Before using make sure 'GunZ' isn't open.

-) Go to 'FGunZ' Folder
-) Find the 'Config.Xml'
-) Right click -> edit
-) Find where it says

<VIDEO>
<WIDTH>1024</WIDTH>
<HEIGHT>768</HEIGHT>
<COLORBITS>8</COLORBITS>
<GAMMA>255</GAMMA>
<FULLSCREEN>TRUE</FULLSCREEN>
<REFLECTION>false</REFLECTION>
<LIGHTMAP>false</LIGHTMAP>
<DYNAMICLIGHT>false</DYNAMICLIGHT>
<SHADER>false</SHADER>
<CHARACTORTEXTURELEVEL>1</CHARACTORTEXTURELEVEL>
<MAPTEXTURELEVEL>8</MAPTEXTURELEVEL>
<EFFECTLEVEL>0</EFFECTLEVEL>
<TEXTUREFORMAT>8</TEXTUREFORMAT>
<NHARDWARETNL>false</NHARDWARETNL>
</VIDEO>


DON'T CHANGE YOUR WIDTH OR HEIGHT OR GUNZ WILL NOT START!

-) Replace it with whats above
-) Start GunZ.

Note: Basically what this is used for is to reduce screen lag for some people.
For others it also helps them with focusing on the enemy. Or just doesn't help you at all...
DO NOT CHANGE YOUR SETTINGS IN-GAME OR THEY WILL REVERT TO ORIGINAL SETTINGS.