Confirmed.

And please, make regular ammo work with supressor.

Confirmed, also happens when you try to move towards/open a non-enterable door on the second floor of the Military Building (Balota Airstrip, Green Mountain..)

Confirmed. Also noticed this issue on every item I assigned to 1-0 hotkeys.

It would be cool if doors could hold back zombies for some time (as they scratch and punch it until it's open)

Confirmed.

Confirmed. Using [Purification Tablets] on a watter bottle/canteen will completely consume the first, no matter how much of it was left (94%, 27%, etc). Tried a lot of times.

Happens to a friend of mine, when coming back from desktop to game.

Confirmed.

And please, make regular ammo work with supressor.

Confirmed.

Confirmed.

Confirmed.

See the TEC building upper corridor, you can use the [open door] icon on a door there, but it opens a door on the floor bellow it.

Confirmed. I understand DayZ team wants players to strive for survival (which is great) but dying so fast after eating/drinking is just bad. People can survive weeks without eating and a couple of days without drinking water.

My suggestion: Instead of killing (reducing "HP"), hunger and thirst should make players weaker, slower and/or "sick" over time. Of course, at later stages starvation kills.

Confirmed. The same thing happened to me and two friends of mine, tough I don't know how to replicate it.

We were killed during a gunfight, then we disconnected and logged in another server to start over, but we were surprised to see our character and gear were intact.

Confirmed.

Confirmed.

Fighting/sneaking/avoiding zombies should be a game on its own in DayZ, funny and challenging, not annoying and clunky as it is now.

Confirmed. Sometimes it happens on the main screen too.