Custom fields and "functions" for a slider

Hi. I installed a slider plugin called Pointella Slider. It has an option to customize the content of the "Post Meta Info" in the slider's navigation. I want to use a custom field I set up in Athaupla for one of the post meta info items. I named this custom field "Author".

The slider is asking me to enter the "function name" and I put in "Author" (without the quotes).

It then asked for the "function parameters" and I put in "field=display_name" (without the quotes).

Am I doing something wrong? It is not displaying anything.

Thanks!
Emanuel