Dan thanks for the report on your scope , star testing can be influenced by weather variables on a given night so try again on a few different nights {this download might help
http://aberrator.astronomy.net/html/download.html} i think turned down edge is more of a Abberration that affects mirrors . The ED should be able to push to the boundries so if it is a indication of a problem definetly dont accept it get onto the dealer and send a direct to william yang through the WO site or the WO williams yahoo group and try the gurus at the Cloudy night forums .