sauceball,
As far as I know, Stage 1 and Stage 2 are just there to decide whether you should reach Stage 3 and they don't count directly towards the decision.
However, I know they can ask you about things which you might have got wrong in the motivation papers, or the results of the personality tests so Stage 3 is not totally devoid of previous stuff!
Good luck - feel free to PM me if you have any random questions.