McKay struck the only goal of the game in 20 minutes as skipper Richie Foran's speculative shot from outside the box was deflected by Calum Butcher into McKay's path.
The Northern Ireland ace pounced on the opportunity, held off Arabs skipper Sean Dillon, and calmly lofted the ball over the advancing Cierzniak for a classy opener.
The Highlanders should have won by more but will be satisfied with their impressive start, while their lacklustre opponents look as though they have a lot of work ahead of them this season.
Partick Thistle produced a superb display to beat Ross County 3-1 at Global Energy Stadium.
Steven Lawless hit a double early in the second half after Kris Doolan had opened the scoring.
Graham Carey grabbed a consolation goal for County with a deflected shot but there was no way back.
Thistle forced the first corner of the match in the 18th minute and Gary Fraser's delivery was knocked on by Conrad Balatoni for Doolan to scoop the ball into the net at the back post.
The visitors took advantage of some sloppy play in the 53rd minute and after Stuart Bannigan was denied, Lawless was on hand to drill home the rebound.
County kept plugging away and they pulled one back in the 71st minute when Carey scored with a deflected shot from outside the area.
Thistle new boy Kallum Higginbotham had the ball in the net in the final minute but was ruled offside.