Generally speaking - the more recent Prelim tests do not have a halt at X as the first thing you do - which is great cos you don't disrupt the horse.
I can't remember the specific tests - but all the prelim ones usually have walk, trot and canter on each rein, and at least one free walk on a loose rein. 20m circles at trot and canter. You may get a change of rein in walk through X via two half 10 metres circles, and you may also get a half circle and return type movement in trot. Maybe a trot serpentine ?
Canter wise - I think the toughest it gets is canter across the diagonal and trot at the quarter marker.
The 'more difficult' ones will ask for a few lengthened strides in trot eg across the diagonal.
I have not done a Novice test for a very long while, so I'll leave that to someone else