These are different things.
First of all, the NGRE in OH 2.5 does not support Rules DSL. You can write using ECMAScript (i.e. JavaScript) or you can install and use Python or Groovy. You cannot do anything with Rules DSL from PaperUI (NOTE: Rules DSL is fully supported in the the UI in OH 3).
Unfortunately the term “Script” is overloaded. In PaperUI a rule consists of zero or more triggers, zero or more conditions, and zero or more actions. One type of action is a “Script Action”. If you were writing a rule in a .rules file, this would be the code that goes between the then and the end. It has nothing at all to do with Scripts (blocks of Rules DSL code that you can call from rules).
So you either need to write this in a .rules file (Rules | openHAB) or you need to write the rule using JavaScript. Or you need to upgrade to OH 3.