Andy, you're supposed to click as soon as the 'possible' hazard appears and then again as it develops.. but that doesn't work..
When you see the 'possible' hazard click, then keep clicking the mouse every second or so (not too fast or it will error) untill the hazard is over...
Also, it's
50 to pass for HGV.. 40 is for car drivers.. I got 60 on the day, but only by following the above...
HTH's
Luv
Chrisie...