[Plugin: Business Directory Plugin] 404 error for listing

When I click on a listing to go to the detail view, I get a 404 error. This occurs at every link to the detail view I can find including from the post in the back end. It seems like it must be a permalink issue.
My site is http://transylvaniawellnessalliance.com. Click on “Practitioners” to see the directory.

Thanks

http://wordpress.org/extend/plugins/business-directory-plugin/