Since the last two updates, Minecraft takes a long time to load, long time to generate world, displays and treats physics incorrectly, then crashes almost instantly back to home screen

My lad loves this game and his worlds are on this device, he is really gutted that he can't play at the moment and I hope you can fix this soon

I saw a new update today so I have come down whilst he's asleep to install it and hope it fixed the problem, but unfortunately it persists