Heat oven to 375°F. Cut each tortilla into 8 wedges. Place on baking sheets in a single layer. Spray with a light coating of cooking spray. Sprinkle generously with cinnamon-sugar. Turn tortilla wedges. Spray other side with a light coating of cooking spray; sprinkle with cinnamon-sugar. Bake 9 to 10 minutes or until crisp.
Stir sweetened condensed milk, apple pie spice and salt in 3-quart microwave-safe glass bowl. Microwave on high 2 minutes. (Milk will boil and rise in bowl during cooking.) Stir. Microwave on medium-low (30 percent power) an additional 8 to 9 minutes, whisking every 3 minutes, until slightly thickened.
Place half of tortilla chips on serving platter. Drizzle with half of hot caramel sauce. Top with 1 apple, 1/3 cup nuts and 1/4 cup toffee bits. Top with remaining tortilla chips, apple, nuts and toffee bits. Drizzle remaining caramel sauce over nachos. Serve immediately.
