Program: 10375
Project: 10375
Buggy source:
@Override public void execute(ScriptEntry scriptEntry) throws CommandExecutionException {
  Element action=scriptEntry.getElement("String_Node_Str");
  Element type=scriptEntry.getElement("String_Node_Str");
  Element id=scriptEntry.getElement("String_Node_Str");
  dScript finish_script=(dScript)scriptEntry.getObject("String_Node_Str");
  dB.report(getName(),action.debug() + (type != null ? type.debug() : "String_Node_Str") + id.debug()+ (finish_script != null ? finish_script.debug() : "String_Node_Str"));
  List<aH.Argument> arguments=(ArrayList<aH.Argument>)scriptEntry.getObject("String_Node_Str");
switch (Action.valueOf(action.asString().toUpperCase())) {
case NEW:
    if (denizen.getListenerRegistry().getListenersFor(scriptEntry.getPlayer()) != null && denizen.getListenerRegistry().getListenersFor(scriptEntry.getPlayer()).containsKey(id.asString().toLowerCase())) {
      dB.echoError("String_Node_Str" + id.asString() + "String_Node_Str");
      break;
    }
  try {
    denizen.getListenerRegistry().get(type.asString()).createInstance(scriptEntry.getPlayer(),id.asString()).build(scriptEntry.getPlayer(),id.asString(),type.asString(),arguments,finish_script,scriptEntry.getNPC());
  }
 catch (  Exception e) {
    dB.echoDebug("String_Node_Str");
    e.printStackTrace();
    try {
      denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).cancel();
    }
 catch (    Exception ex) {
    }
  }
break;
case FINISH:
if (denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()) != null) denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).finish();
break;
case CANCEL:
if (scriptEntry.getPlayer() != null) {
if (denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()) != null) denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).cancel();
break;
}
 else denizen.getSaves().set("String_Node_Str" + scriptEntry.getPlayer().getName() + "String_Node_Str"+ id,null);
}
}

Fixed version (ground truth):
@Override public void execute(ScriptEntry scriptEntry) throws CommandExecutionException {
  Element action=scriptEntry.getElement("String_Node_Str");
  Element type=scriptEntry.getElement("String_Node_Str");
  Element id=scriptEntry.getElement("String_Node_Str");
  dScript finish_script=(dScript)scriptEntry.getObject("String_Node_Str");
  dB.report(getName(),action.debug() + (type != null ? type.debug() : "String_Node_Str") + id.debug()+ (finish_script != null ? finish_script.debug() : "String_Node_Str"));
  List<aH.Argument> arguments=(ArrayList<aH.Argument>)scriptEntry.getObject("String_Node_Str");
switch (Action.valueOf(action.asString().toUpperCase())) {
case NEW:
    if (denizen.getListenerRegistry().getListenersFor(scriptEntry.getPlayer()) != null && denizen.getListenerRegistry().getListenersFor(scriptEntry.getPlayer()).containsKey(id.asString().toLowerCase())) {
      dB.echoError("String_Node_Str" + id.asString() + "String_Node_Str");
      break;
    }
  try {
    denizen.getListenerRegistry().get(type.asString()).createInstance(scriptEntry.getPlayer(),id.asString()).build(scriptEntry.getPlayer(),id.asString(),type.asString(),arguments,finish_script,scriptEntry.getNPC());
  }
 catch (  Exception e) {
    dB.echoDebug("String_Node_Str");
    if (denizen.getListenerRegistry().get(type.asString()) == null)     dB.echoError("String_Node_Str");
 else     e.printStackTrace();
    try {
      denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).cancel();
    }
 catch (    Exception ex) {
    }
  }
break;
case FINISH:
if (denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()) != null) denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).finish();
break;
case CANCEL:
if (scriptEntry.getPlayer() != null) {
if (denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()) != null) denizen.getListenerRegistry().getListenerFor(scriptEntry.getPlayer(),id.asString()).cancel();
break;
}
 else denizen.getSaves().set("String_Node_Str" + scriptEntry.getPlayer().getName() + "String_Node_Str"+ id,null);
}
}