The Cobblers comfortably won the match with goals in each half from Thornton and substitute Michael Jacobs.
Crosby said: "It was an opportunity for us to move up the table with so few other games being played, and I'm pleased we did so.
"We started very well, and when we scored so early on I thought we might go on to score more goals. But Stockport came back well until we got on top again in the second half.
"We were a bit sloppy at times, but the team performed well and we got the result we deserved. We've played very well in several games this season and not got the results, so it was pleasing to get it in this game.
"Kevin Thornton has got great ability and scored a super goal. There are times when you need a flair player in centre midfield and he links up well with Abdul Osman, who has been outstanding this season."
Source: PA
Source: PA