Seeing as you asked the questions, i've had a look.
1) 1st initial long ball from Hunt (I presume at Full back) - when Hooper comes into view he looks off by a yard, but we have to assume he's just run from an onside position with good timing and anticipation.
2) Header to Wallace - yes, true Hooper is stood offside but the header was clearly to Wallace, so Hooper deemed not active.
3) At the point Wallace stretches with the outside of his left foot and centres it, Hooper has gone onside because Jake has gone slightly past him.
4) Jake makes the mistake of trying to head a ball,not expecting the quick movement and then finish from Hooper.
Just looked a good goal as against poor defending. If we want to criticise, we could call if hoooooof ball from Hunt.
We just have to accept the new rules are to make the game more exciting and to get more goals in a game. Hooper was one of 2 or 3 piggy players that did ok today.
UTB