diff --git a/guilib/include/rtabmap/gui/PreferencesDialog.h b/guilib/include/rtabmap/gui/PreferencesDialog.h
index 22dfd8e9..6fc26cb6 100644
--- a/guilib/include/rtabmap/gui/PreferencesDialog.h
+++ b/guilib/include/rtabmap/gui/PreferencesDialog.h
@@ -37,6 +37,7 @@ class QGroupBox;
 class QMainWindow;
 class QLineEdit;
 class QSlider;
+class QProgressDialog;
 
 namespace rtabmap {
 
@@ -155,6 +156,7 @@ private slots:
 	void updateKpROI();
 	void changeWorkingDirectory();
 	void changeDictionaryPath();
+	void readSettingsEnd();
 
 protected:
 	virtual void showEvent ( QShowEvent * event );
@@ -175,9 +177,6 @@ protected:
 
 private:
 	bool validateForm();
-	bool validatePanelGeneral();
-	bool validatePanelFourier();
-	bool validatePanelSurf();
 	void setupTreeView();
 	void setupSignals();
 	void setupPredictionPanel();
@@ -188,6 +187,7 @@ private:
 	void addParameter(const QObject * object, const QString & value);
 	void addParameters(const QGroupBox * box);
 	QList<QGroupBox*> getGroupBoxes();
+	void readSettingsBegin();
 
 protected:
 	rtabmap::ParametersMap _parameters;
@@ -201,6 +201,8 @@ private:
 	//For Bayes filter prediction parameters
 	QList<QSlider*> _predictionLCSliders; // Sliders used to setup the prediction
 	bool _predictionPanelInitialized;
+
+	QProgressDialog * _progressDialog;
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(PreferencesDialog::PANEL_FLAGS)
diff --git a/guilib/src/MainWindow.cpp b/guilib/src/MainWindow.cpp
index 3bc7d8e6..2cdd79df 100644
--- a/guilib/src/MainWindow.cpp
+++ b/guilib/src/MainWindow.cpp
@@ -49,6 +49,7 @@
 #include <QtGui/QDesktopServices>
 #include <QtCore/QStringList>
 #include <QtCore/QProcess>
+#include <QtGui/QSplashScreen>
 
 #define LOG_FILE_NAME "LogRtabmap.txt"
 #define SHARE_SHOW_LOG_FILE "share/rtabmap/ShowLogs.m"
@@ -79,6 +80,12 @@ MainWindow::MainWindow(PreferencesDialog * prefDialog, QWidget * parent) :
 
 	initGuiResource();
 
+	QPixmap pixmap(":images/RTAB-Map.png");
+	QSplashScreen splash(pixmap);
+	splash.show();
+	splash.showMessage(tr("Loading..."));
+	QApplication::processEvents();
+
 	this->setWindowTitle(tr("Constant-Time Appearance-Based Mapping"));
 	this->setWindowIconText(tr("RTAB-Map"));
 
@@ -227,6 +234,8 @@ MainWindow::MainWindow(PreferencesDialog * prefDialog, QWidget * parent) :
 	this->applyPrefSettings(PreferencesDialog::kPanelAll);
 
 	_ui->statsToolBox->setWorkingDirectory(_preferencesDialog->getWorkingDirectory());
+
+	splash.close();
 }
 
 MainWindow::~MainWindow()
diff --git a/guilib/src/PreferencesDialog.cpp b/guilib/src/PreferencesDialog.cpp
index 02ab646e..74b895da 100644
--- a/guilib/src/PreferencesDialog.cpp
+++ b/guilib/src/PreferencesDialog.cpp
@@ -205,6 +205,10 @@ PreferencesDialog::PreferencesDialog(QWidget * parent) :
 
 	_obsoletePanels = kPanelAll;
 	_initialized = true;
+
+	_progressDialog = new QProgressDialog(this);
+	_progressDialog->setWindowTitle(tr("Read parameters..."));
+	_progressDialog->setMaximum(2);
 }
 
 PreferencesDialog::~PreferencesDialog() {
@@ -744,33 +748,7 @@ void PreferencesDialog::writeCoreSettings(const QString & filePath)
 
 bool PreferencesDialog::validateForm()
 {
-	if(	validatePanelGeneral() &&
-		validatePanelFourier() &&
-		validatePanelSurf() )
-	{
-		return true;
-	}
-
-	return false;
-}
-
-bool PreferencesDialog::validatePanelGeneral()
-{
-	/*if(_ui->general_spinBox_hardThr->value() < _ui->general_spinBox_softThr->value())
-	{
-		QMessageBox::warning(this, tr("Settings validator"), tr("The hard threshold must be bigger than the soft threshold."));
-		return false;
-	}*/
-	return true;
-}
-
-bool PreferencesDialog::validatePanelFourier()
-{
-	return true;
-}
-
-bool PreferencesDialog::validatePanelSurf()
-{
+	//TODO...
 	return true;
 }
 
@@ -781,19 +759,31 @@ QString PreferencesDialog::getParamMessage()
 
 void PreferencesDialog::showEvent ( QShowEvent * event )
 {
-	QProgressDialog statusDialog;
-	statusDialog.setWindowTitle(tr("Read parameters..."));
-	statusDialog.setLabelText(this->getParamMessage());
-	statusDialog.setMaximum(2);
-	statusDialog.setWindowModality(Qt::WindowModal);
-	statusDialog.show();
+	this->readSettingsBegin();
+}
+
+void PreferencesDialog::readSettingsBegin()
+{
+	_progressDialog->setLabelText(this->getParamMessage());
+	_progressDialog->show();
+
+	// this will let the MainThread to display the progress dialog before reading the parameters...
+	QTimer::singleShot(10, this, SLOT(readSettingsEnd()));
+}
+
+void PreferencesDialog::readSettingsEnd()
+{
+	QApplication::processEvents();
 
 	this->readSettings();
-	statusDialog.setValue(1);
-	statusDialog.setLabelText(tr("Reading GUI settings..."));
+
+	_progressDialog->setValue(1);
+	_progressDialog->setLabelText(tr("Reading GUI settings..."));
+
 	this->setupPredictionPanel();
 	this->setupKpRoiPanel();
-	statusDialog.setValue(2);
+
+	_progressDialog->setValue(2); // this will make closing...
 }
 
 void PreferencesDialog::saveWindowGeometry(const QString & windowName, const QWidget * window)
@@ -1587,7 +1577,7 @@ void PreferencesDialog::setHardThr(int value)
 		}
 		else
 		{
-			this->readSettings();
+			this->readSettingsBegin();
 		}
 	}
 }
@@ -1605,7 +1595,7 @@ void PreferencesDialog::setReactivationThr(int value)
 		}
 		else
 		{
-			this->readSettings();
+			this->readSettingsBegin();
 		}
 	}
 }
@@ -1622,7 +1612,7 @@ void PreferencesDialog::setImgRate(double value)
 		}
 		else
 		{
-			this->readSettings();
+			this->readSettingsBegin();
 		}
 	}
 }
@@ -1639,7 +1629,7 @@ void PreferencesDialog::setAutoRestart(bool value)
 		}
 		else
 		{
-			this->readSettings();
+			this->readSettingsBegin();
 		}
 	}
 }
@@ -1656,7 +1646,7 @@ void PreferencesDialog::setTimeLimit(double value)
 		}
 		else
 		{
-			this->readSettings();
+			this->readSettingsBegin();
 		}
 	}
 }