I'd say the main reason for being forward in the bottom position is because you're jumping back so much. You can really see it on the last one in your video.
It looks like it all originates from the 1st Pull. You look down and stay way over the bar which may cause your weight to shift forward over the foot. Then you arch way back in the 2nd Pull and your feet slide back. You need to stay more balanced during the 1st Pull and think about extending UP rather than flinging your head BACK.
Also, when you shift your feet to receive the bar overhead, think about bringing the knees up rather than pulling your heels back. You can also put a 1-inch mat or piece of wood or something behind your heels for extra motivation to not jump back.
Dropping a knee down when you receive a heavy Snatch can quickly turn into a habit so I would work on just dropping the weight down it in front if it's forward.