http://geck.gamesas.com/index.php/SetGameSetting is a console-only function. If you want to change a game setting in an actual script, you'll need to use a
FOSE function - either http://fose.silverlock.org/fose_command_doc.html#con_SetGameSetting or http://fose.silverlock.org/fose_command_doc.html#SetNumericGameSetting. Note that only http://fose.silverlock.org/fose_command_doc.html#SetNumericGameSetting will accept a variable as its second parameter.
Cipscis