Quote from Tiger
When playing STFBall_Beta2, the ball will sometimes desync from the clients.
The ball can easily desync when there is other actors on the map (like map04), and the ball can sometimes desync when pushing the ball and kicking it at the same time. If you don't really get rough with the ball, the ball wont really desync; however if you get rough with the ball or have 8+ player you will see the ball desync at times.

Actor DummyPlayer 32767
{
    Health 2147483647
    Radius 16
    Height 56
    Mass 100
    +SOLID
    +SHOOTABLE
    +DROPOFF
    +SLIDESONWALLS
    +CANPASS
    +FLOORCLIP
    +WINDTHRUST
    +TELESTOMP
    +NOBLOCKMONST
    States
    {
    Spawn:
        TNT1 A 0
        TNT1 A 0 A_SpawnItemEx ("ServerSideActor", 0, 0, 0, 0, 0, 0, 0, 0, 0)
        TNT1 A 0 A_SpawnItemEx ("ClientSideActor", 0, 0, 0, 0, 0, 0, 0, SXF_CLIENTSIDE, 0)
        TNT1 A 1
        Loop
    }
}

Actor ServerSideActor
{
    +NOBLOCKMAP
    +NOGRAVITY
    States
    {
    Spawn:
        PLAY A 2 Bright
        Stop
    }
}

Actor ClientSideActor
{
    Translation 2
    +NOBLOCKMAP
    +NOGRAVITY
    States
    {
    Spawn:
        PLAY A 2 Bright
        Stop
    }
}