In a small bowl, stir together the cherries, amaretto, almond extract and salt. Sprinkle a 9-by-5-inch loaf pan with water and line it with a 15-inch sheet of plastic wrap lengthwise, pressing it into the corners and up the sides of the pan; allow the excess to overhang. Sprinkle a third of the cookies into the pan. In a large bowl with an electric mixer, beat the cream and condensed milk to stiff peaks, then fold in the cherries and their liquid. Spread half the cream mixture in the pan, then sprinkle with half of the remaining cookies. Cover with the remaining cream mixture and sprinkle with the remaining cookies. Press the plastic-wrap overhang directly against the surface. Freeze for at least 4 hours or up to 1 week. To serve, invert the semifreddo out of the pan onto a platter and remove the plastic wrap. Let stand for 15 minutes, then cut into slices.