Copy and paste this into your file:
#!/bin/bash
xgamma -gamma 1.6
./Quake3-UrT.x86_64
xgamma -gamma 1
Only the first line HAS to have the #. :)
If this is not working try this:
#!/bin/bash
xgamma -gamma 1.6
./Quake3-UrT.i386
xgamma -gamma 1
If this is not working either please open a terminal and go to your folder where the game is located.
Then type
./UrT_start.sh
You might get an error. Please post this here so we can see what's wrong. :)
If it says it doesn't know UrT_start.sh make sure you are in the correct directory and that the file is executable.
Anything else just post it here.
I use the same script so don't give up I know that it works but it has to be setup correctly. :)