Anchor Pane is not showing in some machines

The following pictures are with the same jar on different machines with Java 7 update 11 on both machines

without the pane ( https://www.filesanywhere.com/fs/v.aspx?v=8a726b895d6675ab73a2 )
with the pane ( https://www.filesanywhere.com/fs/v.aspx?v=8a726b895d676fb19fa8 )
what i've found this far is that the components on the first picture are there... but all of them are completly transparent or blocked by "something"... the weird think is that is the same jar with different behaivour on different machines.

The panel is being added with

URL fxml = getClass().getResource("/mx/gob/scjn/iusjfx/presentacion/consultas/palabras/PalabrasTesis.fxml");
                    generador = new FXMLLoader(fxml,res);
                    generador.load();
                    generador.load();
                    Parent root = generador.getRoot();
                    palabrasTesisCtl = generador.getController();
                    panelBusqueda.getChildren().clear();
                    panelBusqueda.getChildren().add(root);