How can I modify the navigation bar to suit my needs?

I am using ED for many types of discussions on my site. I use ED categories and ACL to both organize discussions and to restrict access to these discussions based on 1) the subscription level of the user and 2) the topic area for the discussions (support discussions vs community discussions). Users gain access to ED through menu items and I intend to appropriately narrow the breadth of discussions at that point to achieve a simple and clean UI experience just like I get each time I access the support forum here (BTW, is your navigation module and template one that I can access/purchase?).

I would like to use the available Navigation Module but can't now because it lists ALL of my categories. Can you offer a hack such that the Navigation Module could be "modal" based on the current category?

For example, mod_easydiscuss_navigation.php detects the current category a user is browsing. Could the Navigation Module then display only the sub-categories of that category? In this way the menu item linked to an EB category would result in the display of the Navigation Module showing ONLY those sub-categories.

I suppose my next wish-list would be for the "Ask a Question" button be similarly modal such that it ONLY lists those categories that are displayed in the Navigation Module. But I'm guessing that would require more than a quick hack ...