Combine all cereal, coconut and nuts in a large bowl.In a medium saucepan, heat the butter, sugar, corn syrup and salt over medium heat. Once it begins boiling, set a timer and boil for 3 minutes, stirring often.Once it's done, remove from heat and pour mixture over cereal. Stir well, so that everything is coated. Let sit for about 5 minutes, then add M&M's and gently stir once more. Store in an airtight container.Enjoy!