If she's having difficulty, soften her food by soaking it in water before giving it to her, or conversely, grinding it. If you grind it, still you should mix it with wetter foods, like the yogurt. Use plain, high quality yogurt with active cultures and without sugar. Just put her starter feed in a jar and add water until it is soaked and softened and a bit broken down for her.
Sometimes even the chick starter is a bit big or too much for them, and they need things a little easier to digest for a day or three.
Do I need to separate her from my other chicks or is it OK for all of them? I do have one other that I had to clean it's him earlier today. The others are all doing good.