Program: 30347
Project: 30347
Buggy source:
@Override public void show(){
  stage=new Stage(new ScreenViewport());
  Table table=new Table();
  table.setFillParent(true);
  table.center();
  table.addListener(new InputListener(){
    @Override public boolean keyUp(    InputEvent event,    int keycode){
      if (keycode == Input.Keys.ESCAPE || keycode == Input.Keys.BACK)       if (World.getInstance().getCurrentScene() != null)       ui.setCurrentScreen(Screens.SCENE_SCREEN);
      return true;
    }
  }
);
  stage.setKeyboardFocus(table);
  Label title=new Label(Config.getProperty(Config.TITLE_PROP,"String_Node_Str"),ui.getSkin(),"String_Node_Str");
  table.add(title).padBottom(DPIUtils.getMarginSize() * 2);
  if (World.getInstance().savedGameExists()) {
    TextButton continueGame=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
    continueGame.addListener(new ClickListener(){
      public void clicked(      InputEvent event,      float x,      float y){
        if (World.getInstance().getCurrentScene() == null)         World.getInstance().load();
        ui.setCurrentScreen(Screens.SCENE_SCREEN);
      }
    }
);
    table.row();
    table.add(continueGame);
  }
  TextButton newGame=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  newGame.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      World.getInstance().newGame();
      ui.setCurrentScreen(Screens.SCENE_SCREEN);
    }
  }
);
  table.row();
  table.add(newGame);
  TextButton help=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  help.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      ui.setCurrentScreen(Screens.HELP_SCREEN);
    }
  }
);
  table.row();
  table.add(help);
  TextButton credits=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  credits.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      ui.setCurrentScreen(Screens.CREDIT_SCREEN);
    }
  }
);
  table.row();
  table.add(credits);
  if (EngineLogger.debugMode()) {
    TextButton debug=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
    debug.addListener(new ClickListener(){
      public void clicked(      InputEvent event,      float x,      float y){
        DebugScreen debugScr=new DebugScreen();
        debugScr.setUI(ui);
        ui.setCurrentScreen(debugScr);
      }
    }
);
    table.row();
    table.add(debug);
  }
  TextButton quit=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  quit.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      World.getInstance().dispose();
      Gdx.app.exit();
    }
  }
);
  table.row();
  table.add(quit);
  table.pack();
  stage.addActor(table);
  Gdx.input.setInputProcessor(stage);
}

Fixed version (ground truth):
@Override public void show(){
  stage=new Stage(new ScreenViewport());
  Table table=new Table();
  table.setFillParent(true);
  table.center();
  table.addListener(new InputListener(){
    @Override public boolean keyUp(    InputEvent event,    int keycode){
      if (keycode == Input.Keys.ESCAPE || keycode == Input.Keys.BACK)       if (World.getInstance().getCurrentScene() != null)       ui.setCurrentScreen(Screens.SCENE_SCREEN);
      return true;
    }
  }
);
  stage.setKeyboardFocus(table);
  Label title=new Label(Config.getProperty(Config.TITLE_PROP,"String_Node_Str"),ui.getSkin(),"String_Node_Str");
  table.add(title).padBottom(DPIUtils.getMarginSize() * 2);
  if (World.getInstance().savedGameExists() || World.getInstance().getCurrentScene() != null) {
    TextButton continueGame=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
    continueGame.addListener(new ClickListener(){
      public void clicked(      InputEvent event,      float x,      float y){
        if (World.getInstance().getCurrentScene() == null)         World.getInstance().load();
        ui.setCurrentScreen(Screens.SCENE_SCREEN);
      }
    }
);
    table.row();
    table.add(continueGame);
  }
  TextButton newGame=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  newGame.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      World.getInstance().newGame();
      ui.setCurrentScreen(Screens.SCENE_SCREEN);
    }
  }
);
  table.row();
  table.add(newGame);
  TextButton help=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  help.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      ui.setCurrentScreen(Screens.HELP_SCREEN);
    }
  }
);
  table.row();
  table.add(help);
  TextButton credits=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  credits.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      ui.setCurrentScreen(Screens.CREDIT_SCREEN);
    }
  }
);
  table.row();
  table.add(credits);
  if (EngineLogger.debugMode()) {
    TextButton debug=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
    debug.addListener(new ClickListener(){
      public void clicked(      InputEvent event,      float x,      float y){
        DebugScreen debugScr=new DebugScreen();
        debugScr.setUI(ui);
        ui.setCurrentScreen(debugScr);
      }
    }
);
    table.row();
    table.add(debug);
  }
  TextButton quit=new TextButton("String_Node_Str",ui.getSkin(),"String_Node_Str");
  quit.addListener(new ClickListener(){
    public void clicked(    InputEvent event,    float x,    float y){
      Gdx.app.exit();
    }
  }
);
  table.row();
  table.add(quit);
  table.pack();
  stage.addActor(table);
  Gdx.input.setInputProcessor(stage);
}