I would say definitely flatten your back, get out just a little bit more, and try to give more of a release up his neck. (I know you're already aware of this.)
Honestly, it's not horrid. I think it'll all come back to you very soon after a few rides. As far as the leg sliding goes - when looking at your two point, ask yourself - "if I took the horse away right now, would I be able to stand on my own two feet without falling over?" That's something to really help you think about exactly where your leg lies. It helps me to steady my leg by really stretching into my heel even more so than I already am when I'm jumping. I mean REALLY deep. I make an effort to stretch long and drop my weight in the last few strides before a jump. It helps keep it in place for me, because mine tends to slide back if I haven't jumped in a while.
So, try to flatten by pulling your shoulders down and back and even though it felt like you were really out of the saddle, just try to raise that bottom up a little bit more. (It's only 2'3 so this won't be a huge deal for now.) When I'm looking at him, it doesn't look like you're giving him enough of his head, so try to aim for more of a release. Just by leaning forward out of the saddle a little bit more, it will give you more of a forward position and a better release naturally.
Overall - looks pretty decent! I know it will be perfect with just a little more time. :)it'll all come back to you!
Last edited by kelseyannxo; 07-17-2015 at 02:40 AM.