Sift the flour and salt into a large mixing bowl. Stir in the beer, mixing until smooth. Beat the eggs and egg yolks in a small bowl, add to the batter and whisk until smooth. Add the sour cream and melted butter. Heat a 6 inch saute pan, add a light coating of butter, and make individual crepes until the batter is used up.
Fill center of each crepe with crabmeat mixture. Roll crepes up and transfer them to a shallow buttered ovenproof dish.
In a mixing bowl combine the bread crumbs, oil, garlic, parsley, chives, and Parmesan. Mix well and sprinkle over the filled crepes. Bake in a preheated 400 degree F oven for about 15 minutes or until the top is golden brown. Serve hot.
On top of a double boiler over simmering water combine crabmeat with shallots, mustard, horseradish, salt, pepper, lemon juice, bichamel sauce and mayonnaise. Cook for about 5 minutes until heated through.
Melt butter in a saucepan. Add onion and saute until transparent. Stir in flour and cook over medium heat until a roux is formed. Mix in thyme and nutmeg. In another saucepan, bring milk and salt to a boil. Pour hot milk quickly into the roux and stir until thickened. Simmer slowly for 15 minutes, stirring constantly. Strain the sauce through a fine sieve.