The FEI CCI1* and multiple EV levels offered are the perfect proving ground for developing FEI horses and riders.
The US rider had led after dressage, but slipped to 4th after cross-country before bouncing back; Canadians won the 4*-S and the 2*-L.
The Aussie moved to the top of the leaderboard with both her rides ahead of Canada's Jessica Phoenix and Wabbit following Saturday's cross-country.
After winning the dressage phase of the CCI4*-L the day before, the American celebrated her birthday with another strong test.
Competition got underway with the first day of dressage; the full field of CCI4*-S competitors go up centreline on Friday afternoon.
Entries in the June 5-8 event feature athletes from four countries and include Olympians and the current world number one, Boyd Martin.
The popular Musical Ride will have two performances – June 6 and 7 – at the Bromont Olympic Equestrian Park.
Once again, up to 10 grants of up to $2,500 will be available for talented young riders 25 and under aiming to compete at MARS Bromont in June.
Allison Springer and No May Moon take the CCI4*-L, edging Waylon Roberts and OKE Ruby R; new Laframboise Family Legacy Awards.
An influential Saturday has Waylon Roberts and OKE Ruby R on top in the CCI4*-L and Karl Slezak and Hot Bobo leading the CCI4*-S.