Bad News, Good News for 2 Live Crew: Police vice squads aren't the only ones with a legal bone to pick with the controversial rap group 2 Live Crew. A federal court lawsuit is claiming that the rappers made an unauthorized derivative recording of Roy Orbison's "Oh, Pretty Woman." Acuff-Rose, a Nashville, Tenn., music publishing firm, said Monday that it refused permission to allow 2 Live Crew to record the song. However, a rap adaptation appeared on the group's album, "As Clean as They Wanna Be," the sanitized version of "As Nasty as They Wanna Be." "It's not about talking dirty," said Acuff-Rose spokesman Tom Adkinson. "It's about copyright infringement." The Nashville publishing firm asked for unspecified damages and for the removal of all copies of the album from stores. Spokesmen for the group and its label were not available for comment. . . . Meanwhile, the group also got some good news Monday. The Sacramento district attorney's office said that it did not find "As Nasty as They Wanna Be" to be obscene. The office had launched an investigation after recent moves to make the selling of the album illegal in three Southern Florida counties and in San Antonio, Tex.