custom "visualformatconfig.xml"

System

I know that I can have a custom "visualformatconfig.xml" for a specific workarea. I red that I need to add this javascript BEFORE you create the instance of the editor

eWebEditPro.parameters.config="path to your config";


I have the following in datacapture.cfg
<item name="Introductory Paragraph">
<textarea rows="15" cols="64" external-editor="visualformat" />
</item>
Could you please tell me how I can create an instance of the editor prior to this. Can someone has any examples?