My daughter says she was told to play the sightreading piece through once before playing it to the examiner. I thought you only got to look at it and then play it once. Did she misunderstand what he said or is this normal?

You are allowed to play all or part of it in the 30 seconds preparation time.
It's possible the examiner might have invited her to have a play through.
It's probably a good idea to play at least some of it but it's not compulsary.
I think that people will generally do whatever their teacher has taught them to do for sight reading preparation.

Did the exam go well?

Thanks Sbboa - I am relieved she didn't do anything wrong. She's very good on the notes, timing, rhythm and dynamics but has no concept of key signatures whatsoever and doesn't know whether to play a sharp, flat or natural unless specifically marked within the bar but has a good ear so playing it through once before the real thing would have helped enormously to work out what key it was supposed to be in.

Notmusimum - she will only tell me that it went OK but she made a few mistakes in the scales so I guess nothing too awful happened, thanks for asking.

Fingers crossed for a good result!