THE AFRICAN NATIONAL CONGRESS castigated President F.W. de Klerk Monday for holding informal weekend Cabinet talks on Robben Island, where Nelson Mandela was held for 18 of his 27 years in prison . . . A RESCUE TEAM dug through heavy snow to find four tents but found no trace of 17 Chinese and Japanese mountain climbers missing since Jan. 4 on 22,112-foot-high Mount Meili in China's southwest Yunnan province . . . EIGHT MORE BANGLADESHIS died Sunday in a cold snap sweeping the country, bringing the death toll this month to 50, newspapers said Monday.