Bukkit

Only winner receives winning message when the game ends.
Fireworks should be fired on game win as well as on kill.
Last killed player doesn't lose items on respawn after game ends.
Players spawn at wrong location on certain servers (Naughty plugins...)
Game didn't end for certain user.
Players knocking others off doesn't count as kill
Players take too long to die from void.
Players keep potion effects after game end.
Player files don't update and all values remain at 0 forever.
Winning kill is not counted into database or player files.
The last person to be killed's games played doesn't go up
Scores go down always?

Command to Leave
Double jump/gravity
Remove command access whilst in game.