Using both ListGrid FilterEditors and SearchForm together

Using smartgwtpower-5.0p
Issue is on all browsers, but have used IE11 and Chrome

I am trying to find the best way to filter on a ListGrid using a combination of both a ShowFilterEditor and a DynamicForm (or SearchForm).
I started with an example from the showcase:
http://www.smartclient.com/smartgwtee/showcase/#sql_dynamic_reporting

The issue with that example is that you cannot remove a filter criteria from a field once it is added. You can change it, but you cannot remove it.
For example if you use the example above, the list starts out long. First filter down to date range: 02/27/2009 - 02/28/2009. Click filter and the list is correctly reduced.
Then remove the first date so that it is blank: empty string - 02/28/2009. Click filter and the list items do not change, the old filter value still applies.

In my example I am using Text fields (not Dates) and the Criteria on the field is not clearing when the FormField is blanked out.

Thanks for your help!