Most of the time people are dissapearing, or I shoot them ten times and they appear behind me while I die. People behind me don't show up on my lil map.

yep i'm seeing this happening a lot lately. I think it's not new, it's just due to new people from different locations coming into the game.
So people from south america has a bad internet connection with the server, which is located at the US. Asian countries depends, some fast some slow... Europeans, same problem... as soon as I see enough people I'll have to add an additional server to where they can connect.

So now a certain player is able to take off straight up, then the same person shoots a mega machine gun from parachute, faster than planes shoot!!! When I shoot this person down, as soon as they push jump, they shoot a thousand bullets and I never get anywhere!!

Nah cuz everything else is going fine. I'll shoot him down n as soon as that parachute appears, his gun even sounds beefy as heck.

hmm have his name in game?
i can check what version he is using with that info