Mix together cereal, crackers, peanuts and pretzels in a large bowl that has been sprayed with cooking spray.
Combine sugar, corn syrup and butter in saucepan over medium-high heat. Stirring frequently, bring to boil and cook for 1 minute. Remove from heat and add vanilla and food colorings (mixture will bubble). Drizzle glaze over snack mix and toss to coat. Gently stir in marshmallows and candy; immediately spread on baking sheet that has been sprayed with cooking spray.
Melt 1/2 cup chocolate chips and oil until smooth. Drizzle over snack mix and refrigerate for 30 minutes to set the chocolate.