trying to gain weight to no avail

From my personal experience... Work out twice a week with 2-3 days in between. One day upper body, one day lower body. 1 Set per muscle group on isolation exercise to complete failure (cant lift another) then 1 post exhaust on compound to failure. Example: 1 set of pecdec, straight into incline bench press.

Within 15 minutes of finishing your very short and intense workout, PB and Honey sandwich + 2 scoops of whey protein shake. Honey is very quick carbs to replenish carbs you just used, and peanut butter is great for protein.

A way to really pack in the calories into your diet is the ultimate bagel/peanut butter combo. Only ONE normal bagel with peanut butter on it is like ~600 cals. Add that onto one of AC powershakes and your set

I say ditch creatine. In the long run the best way is all natural.

Gaining weight - 4-5kcal/day depending how big you are, how fast metabolism is etc, run twice a week light 30 min jog, workout twice a week 2-3 days apart with short intense workouts limitting sets to 1-2 per muscle group, always going to complete failure on each set. Get lots of whey and water into diet.

Cutting up - 3-3.5kcal/day which still depends size/metabolism/etc. Drink lots of COLD water (your body uses calories to warm up cold water once in the body). Keep same whey intake. Run 3 times a week with interval sprints. High intensity sprints at intervals are best way to burn calories. Lift the same.

ALWAYS STRETCH! And if you run on the same day you lift run AFTER you lift. That is my 2cents and what has worked for me.

I'd just chime in and say to remember to intake quality foods.

This means chicken breast, sweet potatoes, tuna...quality protein free from much saturated fat and quality carbohydrates that are not simple sugars.

Wheat bread vs white bread, etc.

Only times you should consume simple sugars or simple carbohydrates would be post-workout in your post-workout meal or in the morning when you have not eaten anything for 8 hours.

The goal here is to gain lean body mass..not fat. Try to bulk cleanly, it will help much.