Hey there! What a beautiful horse! Congrats on your event, how did it go?
What I really see is you are either behind, or ahead. You need to find that happy medium with gorgeous boy. You had it here: Pictures 072 pictures from extreme sports photos on webshots
See how beautiful that picture is - look at where your seat is, look at your leg, your upper body and how round and open your horse is over that fence.
I think you need to go onto the lunge line, and work with no reins. Have someone you trust work with you - so that you can really focus on your horses rhythm.
Jumping is about the rhythm - never the fence. Learn to feel where your horse is, learn to feel where you are. Start to incorporate that feel over trot poles and cavaletti's and really work on just remaining with your horse at all times.
When you master that, work up to x rails.
Just focus on staying over your horses center of gravity, and feeeeel your horse under you. Feeeeel your horses rhythm.
I hope that helps :)