Ko shot a bogey-free final round of 65 to finish at 11-under but she couldn't make ground on South Korea's Eun-Hee Ji who was 17-under for the Swinging Skirts event.
Greensman John Spraggs has tended to the course after a stint at this year's Masters.
Kang has criticised event organisers at the NZ Women's Open today after they allowed play to continue during atrocious weather conditions.
Brooke Henderson shared the course with the rising Kiwi talents before the tournament begins on Thursday.
The All Blacks' first-five was among Kiwi sporting royalty taking part at Windross Farm.