[Plugin: OpenX WordPress Widget] Getting Open X ads to work through custom fields on a page by page

I’ve just installed Open X and this widget and everything is technically fine, using the quicktag I can get banners to appear in the content.

Also using the plugin I’ve been able to add a global header ad but I want to add a banner to the bottom and top of the content using custom_field = {openx:NNN} on a page by page basis.

Is there any way to do that?

https://www.ads-software.com/extend/plugins/openx-wordpress-widget/