Set Criteria based on the input of a form field

Set Criteria based on the input of a form field

1.  I have a form that I want to restrict the "Lookup" data to that the user is authorized to view.
2.  I typically will "Set Criteria" as Distribution_Center == "GLRC".
3.  I want to "Set Criteria" as Distribution_Center == input.Logged_in_User;
4.  When I do this the Set Criteria deluge script states that "Variable 'this' is not declared.
5.  I basically need to figure out how to declare a variable in the "Lookup" field.
 
Any thougths?