Sounds like she was having one of those dreams where people act out things. I cant remember what they are called but very common. Its a type of sleepwalking behaviour.
Could it be because she has lots of energy but her CP stops her running it all off during the day and she is still full of adrenalin when she goes to bed? Does an activity like swimming really tire her out and she sleeps better that night?
Does she cry and get distressed or just wide awake and wanting to play or get up? DGS is sometimes like this and we have to say its still dark and you need to go back to sleep. That when he has a bit of TV because it relaxes him and he will go back off to sleep.
Does the waking follow the 90 minute sleep cycle where sleep is lighter (DGSs does)? Sometimes if this is the case you can get in quickly and reposition and settle before they fully wake. There are some books on sleeping, like 'gentle sleep solutions' which may give some insight.
Its always worth asking whether its siezure related with jerky movements, but I honestly don't think it sounds anything other than a lively child who wakes frequently. Believe it or not there are tons of them out there!
Is she able to play with a simple toy for half an hour and then send herself off to sleep again? My DS could be heard at 5 am bashing and twirling a fisher price toy which fixed to the cot. Then he would just go back to sleep for another couple of hours.
Keep a sleep diary and note what she does in the day and how it relates to the sleep. What has she done when she does sleep well.
Bananas contain a substance which mimics the sleep hormone so a banana or half of one and warm milk before bed?
If you want to risk starting a bad habit but get a good night sleep you can try co sleeping. Thats always a bit of a dilemma for some parents, for others a no brainer as everyone sleeps! Its just a family preference.
We've tried everything including meds and they dont work either! I think your DD is just one of those children (is it 1 in 4?) who don't sleep well. Things do get better over time though. 