* Nationwide the latest Freddy Krueger gore fest may be killing its competition, but business in Orange County has dropped considerably. "Nightmare on Elm Street 4" fell from first place to No. 4 on the local chart, yielding the top spot to Costa-Gavras' "Betrayed," a political thriller starring Debra Winger that has received generally lukewarm reviews. Meanwhile, the summer's other major blockbusters appear to be fading from the local scene. "Cocktail" totaled $33,533 on nine screens for a $3,726 average, putting it ninth in the local running. The summer's two biggies, "Who Framed Roger Rabbit" and "Coming to America," didn't even make the county's top 10. "Roger" stood at No. 12 with a $23,089 total on seven screens, giving it a $3,298 average, while "America" was down to No. 18 with a $7,437 total on four screens for an average of $1,859.