Box squats look ok.
You are dumping it onto your lower back as you lose the brace.
Watch as you go back a bit, your back arches.
Next time, try adding 1/2′ mats about 2-3″ higher for warm ups and making sure you can hit the box with a good shin position and brace.
Pull a mat each set to lower the height as you are able to maintain positions.
Snatch grip looks strong, and pretty good for not getting coaching on it.
Try to keep your shoulders SHRUGGED as high as can at the start and all through the lift.
Snatch grip lat/back position is different than a regular deadlift.
Let’s work on that one thing and then address the rest alter.
Good work.
