Hello,
is it possible on skitter to add all the characters that occure in my words, as single characters to my words?

For example if I have the word "早饭" in my words, can I tell Skitter to add 早 and 饭 without doiing it manually?

Yes, go to Account - Study Settings - Also Add Characters When Adding Words.

There is still a preference for words to come up before characters though.

Thanks a lot =) Thats exactly what I was looking for.

Will it also add the characters from my "old" words now?

EDIT: Sorry, I just did the change and they asked me if I want to add characters from the old lists too. So, problem solved =)

However, in my opinion this doesn't help much because there are so many different meanings for one character I find it best to study them within words.

I prefer to study words, sentences and everything outside Skritter, and use spaced repetition only for practising the characters, individually. I know the words in my head and I practise reading, speaking and writing with words and sentences. SRS is perfect for practising characters, which don't get practised enough in normal language use. And it's good for tones too. But it's too mechanical for all the other aspects of language.