[Plugin: Wp-Directory-List] Expected Functionality

Thank for this plug-in btw. I am attempting to make it fit and I have a couple questions on expected behaviour and a suggestion.

I have top level categories, sub categories and then businesses under them.

How can i display the sub-categories inside let’s say this page:
http://dev.fleming-island.com/businesses/real-estate/

I would like for this page to display the categories who’s parent is the one we are looking at.

Here is an example using the Real Estate parent category:

http://dev.fleming-island.com/business-directory/?v=s&c=Real-Estate&id=7