The Bridgemate scoring system is used at all duplicate sessions. Please remember your EBU number.
You should not bid 3NT. Bid 3H to show 3 card support. As South has only 4 hearts, he shows 3 spades by bidding 3S and North bids 4S.
See below for a discussion of declarer play.
You lead a heart against 7S. Declarer wins and plays QS. Do you cover? If not declarer leads JS. How do you play?