Whisk the eggs and milk together in a bowl. Whisk in the salt, sugar, and flour. Set aside for 30 minutes. Melt about 1/2-teaspoon butter in a nonstick 8 to 10-inch skillet over medium heat. When it foams, pour or ladle in about 2 tablespoons of batter. Lift and swirl the pan so the batter coats the bottom. Set pan on the burner and cook just until set and the underside is lightly browned. Using a spatula or your fingers, flip and cook until the other side is lightly browned. Transfer to a plate and continue with remaining batter.
Blueberry Stuffing: In a bowl, gently fold together the blueberries, maple sugar and sour cream.
Rhubarb Compote: To make the compote, place the rhubarb, orange juice concentrate, sugar, and cornstarch in a saucepan and cook until the fruit falls apart and the mixture thickens.
To serve, place the crepes on a platter and schmear with marmalade. Place a spoonful of the blueberry filling down the center and roll up the crepe. Repeat with remaining crepes. Top off with some rhubarb compote and mint.