The striker took his tally in all competitions to 11 when he converted a 35th-minute penalty, awarded for handball against Danny Boshell.
If County could not argue with the decision, they could rightly feel aggrieved at failing to take anything from a game they dominated, an opinion underlined by the fact that goalkeeper James Spencer made a solitary save all night.
The 10th minute departure of Michael Wolski with a cut calf did little to upset Stockport's early rhythm and it needed a fine, reaction save from Scott Shearer to deny Matt Hamshaw, arriving at the far post to meet Harpal Singh's left-wing cross, the opening goal in the 14th minute.
Despite Stockport's dominance, both territorially and in terms of possession, they produced precious few chances, and frustration must surely have been the overriding feeling among both sets of supporters during the first half.
It came as something of a surprise when Rovers took the lead. Boshell's half-hearted protests reflected the fact he could have few complaints with the decision to penalise him for handball as Ali Gibb attempted to cut the ball back from the byline, and Walker sent Spencer the wrong way from 12 yards.
Stockport responded in admirable fashion, though, and three times went close to levelling matters before the interval.
Boshell sent a drive from 20 yards skidding narrowly the wrong side of Shearer's right-hand upright, Craig Hinton stole Hamshaw's cross off the head of the incoming Jermaine Easter barely two yards from goal, and Singh failed to make sufficiently clean contact with a first-time shot after Easter's cut-back.
Not long into the second period Singh swung over a deep cross for Tes Bramble to head goalwards, but it lacked the power and direction to trouble Shearer.
Easter fired into the sidenetting after direct running and quick feet from Hamshaw and Stockport wasted another chance to restore parity in the 73rd minute.
Shearer's fumble allowing Damian Allen to pick out Bramble at the far post, only for the unmarked striker to head over.
Spencer made his first save of the night 11 minutes from time, narrowing the angle before keeping Junior Agogo's firm left-footed drive out with his legs. It was not a true reflection of the nature of the game.