Archer Community

I am trying to get the value of advanced workflow field called "Workflow Current Node". This is a text field and locked as it is system field. It shows the name of your workflow node. The field is on layout and visible to users. I tried with $CM but ...

Has anyone used a custom object to get current user name and update it in a text field.I am working in Advanced Workflow and trying to get the name of the user who click the Approve button so that I can reflect it in a text field called Approver.