Leatherhead remain fourth but are now six points behind Faversham and only just ahead of a group of teams chasing a play-off spot.
Crawley Down moved back into fifth place, one of three teams trailing the Tanners by a single point, with a 3-2 home win over Chipstead. Luke Blewden gave the Anvils an early lead which Craig Richards doubled moments before the interval.
Chips rallied with two goals in three minutes midway through the second half, Jason Goodchild and Joe Nwoko the men on target, but Blewden struck again with nine minutes left to settle it.
Sittingbourne were held to a 1-1 home draw by Whitstable and slipped back to sixth because they have scored two fewer goals than the Anvils.
Nick Treadwell put the hosts ahead just after half-time, injuring himself in the process, and Danny Williams replied in the 69th minute.
Hythe are seventh, level on points with the two sides above them, after Ronnie Dolan’s 74th-minute goal earned a 1-0 home win over bottom club Three Bridges, who are now ten points adrift.
That is because Walton Casuals, in 21st place, chalked up their first home win of the season at the 15th attempt. Their previous efforts on home turf had produced four draws and 10 defeats.
Kwabena Agyei put them ahead after 26 minutes but it looked as if it would be the same old story when Scott Harris equalised just four minutes later. Mu Mann emerged as the Casuals hero, scoring two minutes before the interval and again immediately after it.
Back at the top end of the table, Folkestone would have moved into fifth place, and maybe even fourth, with a victory at Merstham. But it was the hosts who scored in the fourth minute of added time to win 2-1.
Joe Holland gave Merstham a 17th-minute lead which they held until eight minutes from the end of normal time, when Josh Burchell levelled it. Then Adrian Stone, just signed from Hastings, popped up with the late, late winner.
Note, by the way, that the six games produced five home wins and a draw, a real rarity in a division where visiting teams have had much the better of things all season.
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