You can set the ConfigFile and ToolsFile properties of the RadEditor for SharePint2010 in the WCM field by using the SharePoint Designer. To do so:
Open SharePoint Designer and navigate to the desired page
Open the page and choose Edit Page Layout
Click in the radE:RadHtmlField control so the TagProperties pane is updated with the control
Set the desired properties
Save/Check-In the file so the changes are applied to your site.