Matt Cobb deals with love and murder on the rink In the last installment of the popular Matt Cobb series, the TV network's expert troubleshooter, faces a literal case of cold-blooded murder. At two in the morning, he stands in a Manhattan ice rink, over the grisly body of Dr. Paul Dinkover. The network was supposed to be taping a figure-skating special, and this discovery can't be a coincidence.   The victim is a psychologist, one so thoroughly disagreeable that any number of people could be considered suspects--including beautiful Wendy Ichimi, the show's celebrity skater. But while Cobb's men are mysteriously attacked, he can't stop thinking about the way Dinkover died gripping an American flag, a symbol or clue he can't unravel. And as the leads and tension mount, it will take all of Cobb's strength to keep his cool and remain on his two feet.