Program: 10515
Project: 10515
Buggy source:
@Override public boolean execute(ScriptEntry theEntry) throws CommandException {
  String theScript=theEntry.getScript();
  Integer theStep=null;
  Integer duration=null;
  if (theEntry.arguments() != null) {
    for (    String thisArg : theEntry.arguments()) {
      if (aH.matchesInteger(thisArg))       theStep=aH.getIntegerModifier(thisArg);
 else       if (aH.matchesScript(thisArg))       theScript=aH.getStringModifier(thisArg);
 else       if (thisArg.toUpperCase().contains("String_Node_Str")) {
        int high=1, low=1;
        if (thisArg.split("String_Node_Str")[1].split("String_Node_Str").length == 1) {
          if (aH.matchesInteger(thisArg.split("String_Node_Str")[1])) {
            low=1;
            high=Integer.valueOf(thisArg.split("String_Node_Str")[1]);
          }
        }
 else         if (thisArg.split("String_Node_Str")[1].split("String_Node_Str").length == 2) {
          if (aH.matchesInteger(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[0]) && aH.matchesInteger(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[1])) {
            low=Integer.valueOf(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[0]);
            high=Integer.valueOf(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[1]);
          }
        }
        Random randomInt=new Random();
        if (high - low > 0)         theStep=randomInt.nextInt(high - low + 1) + low;
 else         theStep=high;
      }
 else       if (aH.matchesDuration(thisArg)) {
        duration=aH.getIntegerModifier(thisArg);
        aH.echoDebug("String_Node_Str",thisArg);
      }
 else       aH.echoError("String_Node_Str",thisArg);
    }
  }
  if (theStep == null)   theStep=plugin.getScriptEngine().helper.getCurrentStep(theEntry.getPlayer(),theScript) + 1;
  if (duration != null) {
    Integer oldStep=plugin.getScriptEngine().helper.getCurrentStep(theEntry.getPlayer(),theScript);
    plugin.getServer().getScheduler().scheduleSyncDelayedTask(plugin,new ZapCommandRunnable<String,String,Integer,Integer>(theEntry.getPlayer().getName(),theScript,theStep,oldStep){
      @Override public void run(      String player,      String script,      Integer step,      Integer oldStep){
        if (plugin.getSaves().getInt("String_Node_Str" + player + "String_Node_Str"+ script+ "String_Node_Str") == step) {
          plugin.getSaves().set("String_Node_Str" + player + "String_Node_Str"+ script+ "String_Node_Str",oldStep);
        }
      }
    }
,duration * 20);
  }
  if (!plugin.getScripts().contains(theScript + "String_Node_Str" + theStep))   aH.echoDebug("String_Node_Str");
  if (theEntry.getPlayer() != null && theScript != null && theStep != null) {
    plugin.getSaves().set("String_Node_Str" + theEntry.getPlayer().getName() + "String_Node_Str"+ theScript+ "String_Node_Str",theStep);
    plugin.saveSaves();
    return true;
  }
  return false;
}

Fixed version (ground truth):
@Override public boolean execute(ScriptEntry theEntry) throws CommandException {
  String theScript=theEntry.getScript();
  Integer theStep=null;
  Integer duration=null;
  if (theEntry.arguments() != null) {
    for (    String thisArg : theEntry.arguments()) {
      if (aH.matchesInteger(thisArg))       theStep=aH.getIntegerModifier(thisArg);
 else       if (aH.matchesScript(thisArg))       theScript=aH.getStringModifier(thisArg);
 else       if (thisArg.toUpperCase().contains("String_Node_Str")) {
        int high=1, low=1;
        if (thisArg.split("String_Node_Str")[1].split("String_Node_Str").length == 1) {
          if (aH.matchesInteger(thisArg.split("String_Node_Str")[1])) {
            low=1;
            high=Integer.valueOf(thisArg.split("String_Node_Str")[1]);
          }
        }
 else         if (thisArg.split("String_Node_Str")[1].split("String_Node_Str").length == 2) {
          if (aH.matchesInteger(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[0]) && aH.matchesInteger(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[1])) {
            low=Integer.valueOf(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[0]);
            high=Integer.valueOf(thisArg.split("String_Node_Str")[1].split("String_Node_Str")[1]);
          }
        }
        Random randomInt=new Random();
        if (high - low > 0)         theStep=randomInt.nextInt(high - low + 1) + low;
 else         theStep=high;
        aH.echoDebug("String_Node_Str" + theStep + "String_Node_Str");
      }
 else       if (aH.matchesDuration(thisArg)) {
        duration=aH.getIntegerModifier(thisArg);
        aH.echoDebug("String_Node_Str",thisArg);
      }
 else       aH.echoError("String_Node_Str",thisArg);
    }
  }
  if (theStep == null)   theStep=plugin.getScriptEngine().helper.getCurrentStep(theEntry.getPlayer(),theScript) + 1;
  if (duration != null) {
    Integer oldStep=plugin.getScriptEngine().helper.getCurrentStep(theEntry.getPlayer(),theScript);
    plugin.getServer().getScheduler().scheduleSyncDelayedTask(plugin,new ZapCommandRunnable<String,String,Integer,Integer>(theEntry.getPlayer().getName(),theScript,theStep,oldStep){
      @Override public void run(      String player,      String script,      Integer step,      Integer oldStep){
        if (plugin.getSaves().getInt("String_Node_Str" + player + "String_Node_Str"+ script+ "String_Node_Str") == step) {
          plugin.getSaves().set("String_Node_Str" + player + "String_Node_Str"+ script+ "String_Node_Str",oldStep);
        }
      }
    }
,duration * 20);
  }
  if (!plugin.getScripts().contains(theScript + "String_Node_Str" + theStep))   aH.echoDebug("String_Node_Str");
  if (theEntry.getPlayer() != null && theScript != null && theStep != null) {
    plugin.getSaves().set("String_Node_Str" + theEntry.getPlayer().getName() + "String_Node_Str"+ theScript+ "String_Node_Str",theStep);
    plugin.saveSaves();
    return true;
  }
  return false;
}