SNOW FELL across much of the nation's midsection and the Rockies Friday, and bitter cold and high winds pushed wind chills to 50 degrees below zero in northern Maine. . . . THE CORRUPTION TRIAL of Todor Zhivkov, the Communist dictator who was forced from power in November 1989 after ruling Bulgaria for 33 years, has been set for Feb. 25. . . . AN EARTHQUAKE measuring 6.1 on the Richter scale Saturday shook the Pacific Ocean off Indonesia, but there were no immediate reports of damage or casualties. . . . ABOUT 8,000 people attended an anti-government demonstration Friday in Timisoara, Romania.