Fatal error, Please help.

[Mudbill]

The error indicates that something went wrong upon compiling the script, and that it started at line number 14. You see it says main (14, 53) which means line 14, character 53.

Line 14 is the PlaySoundAtEntity line.

However I don't see any issues with that line myself. Are you sure this is the correct script?
Just in case you can try replacing it all with this (it's the same, just re-formatted):

PHP Code: (Select All)

void OnStart()
{
    PlayMusic("06_amb.ogg", true, 4, 3, 1, false);
    AddUseItemCallback("", "Key_1", "Door_1", "Unlock", true);
}

void Unlock(string &in asItem, string &in asEntity)
{
    SetSwingDoorLocked(asEntity, false, true);
    PlaySoundAtEntity("", "unlock_door.snt", asEntity, 0, false);
    RemoveItem(asItem);
}

void OnEnter()
{

}

void OnLeave()
{

}