He is adorable :)
To start, your lower leg position did not move throughout your entire ride, so kudos! :)
In the first fence on the video you roached your back a bit going over, although its hard to tell but it looks like he may have gotten in a little close so that may be why.
Otherwise, I don't have to many things to pick about. After a few of the fences you stayed forward a little longer, and he was on the forehand a bit. In the one corner his head is tipped to the outside because you are using a lot of outside rein to move him out to the rail, which I know is a hunter thing, but I'd like to see him a little straighter.
Very very cute horse! :)
"The white horse moved like a dancer, which is not surprising: a horse is a beautiful animal, but it is perhaps most remarkable because it moves as if it always hears music."