Rodando ScriptEngine do JavaFX a partir do Java não funciona! :(

List<ScriptEngineFactory> factories = manager.getEngineFactories();

public static void main(String[] args) throws FileNotFoundException, ScriptException {

		File f = new File(filePath); // seto o caminho completo do arquivo Hello.fx
		InputStreamReader reader = new InputStreamReader(new FileInputStream(f));

		ScriptEngineManager manager = new ScriptEngineManager();

		ScriptEngine engine = manager.getEngineByName("javafx");
		engine.eval(reader);

}

import javafx.stage.Stage;
import javafx.scene.Scene;
Stage {
    title : "MyApp"
    scene: Scene {
        width: 200
        height: 200
        content: [  ]
    }
}