Dear maryle,
When you select the "Exclude Images in Active Listings" filter on the Manage Images page, only images that are being used in active listings that were posted through Auctiva should be removed from the list. I'm not aware of any current problems with this feature, but the behavior you have described does not sound right.
If you are still experiencing this problem, I recommend contacting our customer support team using the form on the following page of our site: http://www.auctiva.com/help/requesthelp.aspx
Please be sure to include the name of at least one specific image that is not being used in any active listings but is being removed from the list when you enable this filter when you contact them about this.
-Mike