Stories of computers "locking" up and "looping" are correct. I went in last Thursday and saw it all - thankfully my computer was OK. The day started at 08.30am and was meant to finish at 4.30pm. However most people finished at around 5.30 - 6.00pm. Some even went to 7.30pm cause their computers had to be restarted (due to the above) and hence start again on what ever test they were up to.
There are 10 positions for the training course starting next January. 100 people are being tested for these spots.