Hallo
Now rumour has it that the computer simulated test of preventing dots from colliding is not as important as the first couple of computer tests which involved sorting shapes, numbers, colours and knowing your left and right. all i can say is brush up on your maths and make the most of the practice sessions. and with the dots going across the screen, prevent as many collisions as you can but think everyone has a couple (i stand back if anyone managed to have none!) but think it is there more to see how you cope with a collision - as in go to pot and be useless for the rest...
with the personnel one - well its not very nice. the technical one, just try to learn as much as you can. i did - i literally spent hours and hours on it and in the end managed to prove my knowledge on all kind of crazy things.
best of luck and if you want any futher aid just let me know...