Beat the egg yolks until thick and lemon-colored. Stir in one-quarter cup of the sugar and the vanilla and almond extracts. Set aside.
Melt the butter in a saucepan. Stir in the flour and mix until smooth. Add the milk and cook over low heat, stirring constantly, until thick. Gradually stir in the egg-yolk mixture.
Combine the shredded apples with the lemon juice and cookie crumbs and fold into the egg-yolk mixture.
Beat the egg whites until soft peaks are formed. Gradually add the remaining sugar and continue beating until stiff. Gently fold the meringue into the apple mixture. Turn into an ungreased one-and-one-half-quart casserole or baking dish. Set in a pan of hot water and bake for about one hour, until done. Serve at once with lemon-nutmeg sauce.