Workflow Action Script context preferences issue

Guys I have a company level custom preference :
custscript_nbs143_gw_cancelled_adminfee

It's a list field and it's set to that of an item.
I'm trying to reference the id of the item selected through a work flow action script.
This is what I'm coding :

var context = nlapiGetContext();  var can_afee = context.getPreference('custscript_nbs143_gw_cancelled_adminfee'); 

I've also tried

var can_afee = context.getSetting('SCRIPT','custscript_nbs143_gw_cancelled_adminfee');

and I've tried using

var test = nlapiLoadConfiguration('companypreferences');

and then

 var theID = test.getFieldValue('custscript_nbs143_gw_cancelled_adminfee');

For all of the above my variable is "null".