Congrats on taking in a rescued grey, you will find that most greys fit the description of being afraid of fast movement, they are by nature very cautious of anything new and different.
I would give her plenty of time to settle into her new home, don't rush her, it takes time for a grey especially one who has had a previous home to feel comfortable and she has to come to trust you to feel secure.
Maybe she needs some help with playing with toys, put some in her cage and play with them yourself to show her what to do with them, make out like you are having a great time and it will entice her to join in.