I failed at stage 4 mate... CTC then offered me to reapply in 6 months and I finally went through it and I'm flying to NZ in 10 days.
I knew at the first attempt I hadn't made it but I didn't crash the sim... It's all about your accuracy. If you are asked to turn right with 30 deg bank and maintain 10 000 ft, try not to climb down or miss the required heading.
I personnaly found it the hardest as you have almost done everything and you have to handle a big jet.
Practise your flight sim and try to get used to the 73 panel so that you won't have any big surprise when entering the sim.
The worst is when you think that this day can be the best or the worst of your life so far....
Good luck