Just a few questions more.
1. What is really "cream of tartar".? And what does it do to the royal icing ?
2. How man grams is one butter stick ?
You see we just have 500 gram packets here or 1000 gram.
3. How much is one cup of anything. in deciliters or gram.
In norway we just use this messures.

Hope someone can help me.

I hope this helps you. You can also search the site for certain baking items and what they do.

http://www.joyofbaking.com/ConversionsEquivalencies.html

Cream of tarter works as a thickening agent and works similar to cornstarch. One stick of butter 4oz. equals 113grams. Fluid ounces vary but basically 1 cup equals 8oz. I weigh everything when baking, I find it to be much more consistent and accurate! Hope this helps!

Cakecentral also has a measurement conversion program:
http://www.cakecentral.com/cake_recipes_file-converter.html

Here's something I found on the internet for a definition (google search "cream of tartar")
"cream of tartar
Related: Organic Chemistry

white crystalline powder. Chemically it is potassium hydrogen tartrate, KC 4 H 5 O 6 , the acidic potassium salt of tartaric acid . It is used as the leavening agent in baking powders. An impure form, called tartar or argol, forms naturally during the fermentation of grape juice into wine and crystallizes in the wine casks.

Thanks to you all.
It is sometimes difficult to translate the cup recepies to my own understandeble gram messures.

Your welcome!