Me and those cakes

I love layered cakes. However I su** at making them. I have no idea what I do wrong. I ALWAYS do as the recipe tells me to and they are still not working for me. This following recipe being another example for that.

Classic chocolate cake with vanilla frosting
(recipe from Sweetpaul)
Ingredients:
Dough
240g salted butter
150g brown sugar
50g sugar
1 egg
240ml milk
1 tsp. vanilla
180g flour
1 tsp. backing powder
30g cocoa powder

Frosting
340g sugar
3 egg whites
80ml water
2 tsp. corn sirup
1/4 tsp backing powder
1 tsp vanilla

Prepare:
1. Preheat oven to 190°C.
2. Beat the butter and both types of sugar in a bowl and beat until frothy.
3. Add the egg and mix well.
4. Add milk, vanilla, flour, backing powder and the cocoa powder and again mix well until you have an even dough.
5. Divide the dough equally into two baking forms. (I weighed the dough and the half the weigh into each form.)
6. Bake for about 35 minutes or until a wooden stick comes out clean. Let the cakes cool off afterwards.
7. For the frosting you have to mix the sugar, egg whites, water, corn sirup and backing powder in a metal bowl (because you have to put it onto a water pot.)
8. Put the bowl onto the pot with water in it.
9. You have to mix the mixture well until thick and creamy.
10. Take the bowl from the pan and the vanilla. Then you have to beat the frosting until it cooled off completely. It's supposed to be fluffy.
11. Put one of the cakes onto a cake display and add 1/3 of the frosting and spread evenly. 
12. Put the second cake on top of the first and frosting and put the rest of the frosting on top and on the sides.
13. Add some sprinkles if you like.
14. The cake is supposed to cool off for an hour in the fridge before you serve it.
ENJOY!!

Now this recipe doesn't sound too hard, right? But somehow the cakes didn't went up in the oven and I got some really flat cakes. (First I thought everything vanished into thin air while baking. But when I took them out I could find the really thin cakes!:P) And then the frosting didn't go as planned. I had to add the baking form again because the frosting was leaving the scene...:/ (Even after letting it cool off in the fridge it kept running away...)
I don't know what it is with me and layered cakes. I guess I have to try until one of the recipes I use will be successful! AND I will try this recipe again!!! This has to work!;)

But the you know what?! THE CAKE TASTED AWESOME! So rich of chocolate and very soft and wet on the inside. Really really yummy!:)