I'll try but the work is not in the same order/levels as in the tests in the US:
Introductory - these are walk & trot only tests
Like US 'Intro' level, except that an 'Intro C' was added this year that includes canter.
Preliminary - medium walk, working trot, working canter, 20m circles in trot and walk, free walk on a long rein and halting on the centre line
Like US Training Level.
Novice - serpentines, half 15m circles in canter, a few steps of counter canter and medium trot.
Like US First Level, if the counter canter is on a very easy line, like a shallow serpentine.
Elementary - this is where lateral is introduced. medium canter, leg yield, shoulder-in, rein-back and simple changes, serpintines with 5 loops, some collected trot needed
Um. In the US, leg yield is not introduced at the same level as shoulder in, simple changes and serp 5 loops (what is that 5 loop serp. in, canter or trot?). This would be something like second level.
Medium - it used to be that a double was required from here on up. half-pass, travers, extended walk, half pirouettes in walk and rein-back straight into canter
This would be kind of like third level.
Advanced Medium - Half pass zig-zags, 8 metre circles in canter (collected),4 loop Serpentined in canter with flying changes
This sounds kind of like third level. Are the zig zags at trot?
Advanced
I'm assuming this level is like our fourth level? What's required?
Prix St Georges
same. Though most are conducted under national rules, and only some under international (FEI) rules.
Intermediare I
same
Intermediare II
same
Grand Prix
same