Not a problem of the scenery but, most likely, a duplicate AFCAD for KDFW coming from another product, they usually come with AI traffic packages and, since are made for the default airports, must be removed when using with 3rd party airports.
To find AFCAD duplicates, you can use the free FSX Airport Scanner available here:
http://www.scruffyduckscenery.co.uk/ (click the "Download Center" link )
Fact it's another AFCAD from another product in conflict, can be seen in your screenshot, because when the conflicting runway is visible, it has numbers, while the AFCAD that comes with KDFW doesn't have any numbers/markers, since the runways are fully custom so, it can only be another AFCAD from another product in conflict.