Conor McCarthy and Tony Andreu had put the visitors in a commanding position after only 18 minutes but the Edinburgh outfit managed to bring themselves level before the interval with efforts from Scott Allan and Christian Doidge.
The home side looked more likely to score in a second half that saw the defences come out on top, although both sides had to settle for the 2-2 draw.
The Paisley outfit's afternoon got even better when Andreu doubled their lead. Ilkay Durmus raced clear of David Gray into the area and his low pass was swept first time into the net by the Frenchman.
The home supporters were stunned but Ross' side responded seven minutes later. Martin Boyle got to the byline and his cut back was stroked first time into the net by Allan.
Hibs drew level two minutes before the break when Doidge netted his 15th of the campaign.
McGinn was brought on for Gray at the break to make his Hibs debut but there was brief panic for the hosts when Marciano spilled Durmus' low cross, before the Israeli managed to smother the ball with Andreu ready to pounce.
Ross also brought on Docherty and McNulty and, just before he was taken off, home winger Daryl Horgan flashed a left-footed drive just wide.
McGinn was denied a debut goal in the 70th minute when his header inside the box from Allan's set-piece was expertly tipped around the post by Hladky.
Boyle then watched a deflected shot drift just wide of the post after the Australian international pounced onto Sam Foley's attempted header back to his keeper.