I think it is hardcoded somehow. Atleast, I can't find such settings in the files associated with them (the .rgn files).
Just a heads up! Sonalysts once released an updated set of quickmissions. The old ones are dated juli 2004 in your Scenario folder. The new ones are dated april 2005. You can download them from subguru.com. Just unzip them in the Scenario folder. Though I can't remember what they'd actually fix. Probably just make them work in the first place.
http://www.subguru.com/DW_missions/Q...2005-04-08.zip