Mix together the crumbs, 2 tablespoons sugar, cinnamon, and melted butter.
Press in an even layer into the bottom of an 8 or 9-inch pan with spring-released sides or removable bottom.
Mix cream cheese, the 1/2 teaspoon salt, and rum together until soft and creamy.
Beat the egg whites until they form soft peaks, then gradually beat in the 1 cup sugar to make a meringue.
Fold egg white mixture into the cheese until well blended.
Turn into the crumb-lined pan.
Bake in a 350° oven about 25 minutes.
Remove from oven; increase oven temperature to 450°.
Combine sour cream with sugar and the 1/8 teaspoon salt; spread over top of cake.
Return to oven for 4 to 5 minutes, until cream is set.
Remove from oven and cool until cold.