New Zealand, generally, put in a vastly improved effort following their first round jitters. But it was still not good enough to stop the quartet sliding out of contention in the team competition.
Webby maintained his strong form of Friday, recording eight faults last night, on a bigger, more challenging course to remain a contender in the individual contest.
The top 50 individuals, with Webby placed 30th, advance to tonight's third qualifier which will firstly be culled to 35 before determining the 20 combinations who will jump off for the medals.
Competing in his first Olympics and initially the team reserve, Webby has made the most of the lifeline offered when Daniel Meech was forced to withdraw his injured horse Sorbas two days out from the competition start.
The New Jersey resident and his dark bay mare Sitah again looked impressive with an effortless performance for much of the 13-obstacle course.
Webby blamed rider error for the two glitches in his score last night - a foot in the water at the fourth and knocking off the third of the treble at 11 - but was delighted with Sitah's efforts.
The experienced Bruce Goodin and Yamato just missed out on a top 50 spot after three late fences put paid to a faultless start, leaving the combination in 54th.
Two rails at the treble and knocking a pole off on the final fence consigned Goodin to 12 faults, pushing him out of contention for a spot in the individual competition.
With the best three scores counting towards team totals and the top eight from the 16-nation field progressing to tonight's final, New Zealand struggled to keep their penalties to a minimum.
Anchoring the team, Goodin's late blemishes consigned New Zealand to 14th in the team standings.
Sharn Wordley and the inexperienced Rockville again had their moments. A patchy round which included the dislodging of six fences and a time penalty for not finishing within the 90 second limit proved a costly addition to the team total.
Katie McVean, 22, the youngster of the quartet, and the only rider operating out of New Zealand to be selected in the team, continued to have a harrowing Olympic experience.
A change in equipment and tactics did not improve the Forest's efforts and McVean said the 16-year-old grey gelding just did want to be in the arena. He indicated as much with a demolition job on 10 fences and incurring five time penalties in a difficult Olympic introduction for McVean.
Forest appeared very strong and McVean had trouble pulling him up at the end of the round.
Forest's bit had been changed from the gag used in the first day, to a pelham, and Wordley's Rockville was changed from a pelham to a hackamore.
"It was a step up from two days ago," New Zealand coach Greg Best said.
"We've got one in the top 50 to go through to the next round and one just outside. But there's still a possibility with withdrawals or horses that aren't quite right, that we could end up with two horses going through.
"Kirk's horse is just jumping out of this world. He deserves to be here and it's so ironic that he almost wasn't."