CLM 10 : Agent determination in prescript

Hi Gurus

We are implementing SAP CLM 10.

I am setting up WFs with the built-in editor.

I just need to set up a two-step WF. For each step we have a dedicated User group called "App1" and "App2".

If I understood correctly I just need to add some script lines in the approval activities prescript template to get the agent determined.

I have no script knowledge.

What is the syntax to specify the approver user group?

Thanks in advance