Producer Robert Evans has not had the best of luck with the directors he's been hiring lately. On the set of last year's "The Cotton Club," he ran into such bothersome financial and personal problems with Francis Coppola that production was temporarily halted. And now, conflicts between Evans and Robert Towne have apparently stopped all progress on "Two Jakes," the "Chinatown" sequel written and directed by Towne and coproduced by Evans and Jack Nicholson.

This time, though, the troubles are of a different nature, centering on the fact that Evans is also costarring, playing the bad-guy Jake opposite Nicholson's good-guy Jake. After rehearsals, Towne reportedly decided Evans wasn't quite up to the part, although a couple of decades ago he had appeared in the likes of "The Sun Also Rises" and "The Best of Everything." Towne wanted a new actor, Evans wanted to do the job himself, Nicholson sided with Evans, and early this week the production ground to a halt.

For now, nobody's saying anything more revealing than Paramount's terse official statement: "The production of 'Two Jakes' is not proceeding." . . .

George Romero's third zombie movie, "Day of the Dead" -- his sequel to "Night of the Living Dead" and "Dawn of the Dead" -- is being released this summer. "Return of the Living Dead" is also being released this summer, but that isn't Romero's doing. "Return" is the work of screen writer and filmmaker Dan O'Bannon, and bears only titular relation to Romero's movies. But if the veteran director is worried that O'Bannon might steal some thunder from his own official "Day of the Dead," he isn't showing his concern.

"It's the luck of the draw, and it doesn't bother me," Romero said early this week as he took a break from final sound-mixing chores on the new film. (That morning's typical decision: how loud to make the gunshot when a woman shoots a zombie who's just torn her buddy's throat open.) Plenty of others have already tried to make copycat zombie movies, laughed the director whose first two outings have become grisly classics, overshadowing his more conventional films such as "Creepshow" and "Nightriders," and O'Bannon's is hardly the most blatant offender.

In 1979, he said, immediately after "Dawn of the Dead" opened in Europe under the title "Zombie," a graphic, low-budget imitation called "Zombie II" hit the theaters. (It was released in the United States as just plain "Zombie.") "It really gets crazy, that stuff," said Romero. " 'Cave of the Living Dead,' 'Zombie,' 'Gates of Hell' . . . there's been 30 of them, at least. I saw a few of them. A couple of them had pretty good effects, and a couple of them were actually effective, but none of them seem to have gotten as much attention as my zombie movies . . . "

Ever since last summer's "Ghostbusters," most of Columbia's pictures have been fading quickly from sight. (Anyone remember "New Kids"? It opened early this year and closed a week later in one of the quickest, quietest flops ever.) But the studio's new "Just One of the Guys," a "Tootsie" Goes to High School comedy, has for the past two weeks been the second biggest moneymaking film of a lackluster season.

Last weekend its $2.4 million take trailed Chuck Norris' "Code of Silence" by more than $3 million, but it nonetheless didn't drop nearly as quickly as Burt Reynolds' universally panned "Stick," which fell from first place to seventh. And if that decent showing doesn't lift the spirits at Columbia, it can always take solace in the fact that it was the first studio in town to try the new Coca-Cola. As employes of a division of the Coca-Cola Co., Columbia staffers arrived at work last week to find free six-packs waiting . . .

They'll probably incur the wrath of Oriental actors, but when the filmmakers behind the upcoming "Remo: The First Adventure" tried to find an Asian actor to play an enlightened 82-year-old Korean with otherwordly martial arts skills, they came up short. So director Guy Hamilton hired 52-year-old Caucasian actor-dancer-singer Joel Grey, who got a haircut, took a crash course in all aspects of Eastern life and underwent four hours a day of makeup. The film is based on the "Destroyer" series of pulp adventure novels, which Grey says he hadn't read -- although the elevator operator in his building was familiar with all of them . . .