Thank everyone for your answers!!! They have really helped   

there is no real difference between tracking and turning, when a test says track right/left it just means you turn right/left when meeting the track (usually down centre line) & when they say turn right/left it usually to start a circle or serpentine.... I could be wrong this is just what I've figured through my own experiences with dressage

well.... this is just a guess, cos never seen it in a dressage test b4, but when they say a pony is not 'tracking up' it means that their hind legs are not working enough for them to touch the front hoof print (reach the front hoof) so he is streching and really working his muscles. hope this helped!