diff --git a/Sankore_3.1.pro b/Sankore_3.1.pro
index 1c7b4ae7..aff1440b 100644
--- a/Sankore_3.1.pro
+++ b/Sankore_3.1.pro
@@ -7,7 +7,7 @@ CONFIG += debug_and_release \
    no_include_pwd
 
 VERSION_MAJ = 1
-VERSION_MIN = 28
+VERSION_MIN = 35 
 VERSION_TYPE = b # a = alpha, b = beta, r = release, other => error
 VERSION_PATCH = 00
 
diff --git a/release.linux.sh b/release.linux.sh
index 51742ee3..fffc2450 100644
--- a/release.linux.sh
+++ b/release.linux.sh
@@ -19,7 +19,7 @@ make clean
 rm -rf build/linux/release/
 rm -rf install
 
-QT_PATH="/usr/local/Trolltech/Qt-4.7.3"
+QT_PATH="../Qt-sankore3.1"
 PLUGINS_PATH="$QT_PATH/plugins"
 QMAKE_PATH="$QT_PATH/bin/qmake"
 
diff --git a/resources/sankore.qrc b/resources/sankore.qrc
index 4c7162ef..5b59e338 100644
--- a/resources/sankore.qrc
+++ b/resources/sankore.qrc
@@ -319,7 +319,6 @@
         <file>images/pages_open.png</file>
         <file>images/cache_close.png</file>
         <file>images/cache_open.png</file>
-        <file>style.qss</file>
         <file>images/cache_circle.png</file>
         <file>images/cache_square.png</file>
         <file>images/down_arrow.png</file>
@@ -333,6 +332,7 @@
         <file>images/teacher_close.png</file>
         <file>images/teacher_open.png</file>
         <file>images/teacher_close_disabled.png</file>
+        <file>style.qss</file>
         <file>images/teacher_open_disabled.png</file>
     </qresource>
 </RCC>
diff --git a/src/board/UBBoardPaletteManager.cpp b/src/board/UBBoardPaletteManager.cpp
index e0152975..88693189 100755
--- a/src/board/UBBoardPaletteManager.cpp
+++ b/src/board/UBBoardPaletteManager.cpp
@@ -106,6 +106,11 @@ UBBoardPaletteManager::~UBBoardPaletteManager()
         delete mpLibWidget;
         mpLibWidget = NULL;
     }
+    if(NULL != mpTeacherBarWidget)
+    {
+        delete mpTeacherBarWidget;
+        mpTeacherBarWidget = NULL;
+    }
     if(NULL != mpCachePropWidget)
     {
         delete mpCachePropWidget;
@@ -163,20 +168,20 @@ void UBBoardPaletteManager::setupDockPaletteWidgets()
 
     mpPageNavigWidget = new UBPageNavigationWidget();
     mpPageNavigWidget->registerMode(eUBDockPaletteWidget_BOARD);
-//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpPageNavigWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
-
+//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpPageNavigWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
+
     mpLibWidget = new UBLibWidget();
     mpLibWidget ->registerMode(eUBDockPaletteWidget_BOARD);
     mpLibWidget ->registerMode(eUBDockPaletteWidget_DESKTOP);
-//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpLibWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
+//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpLibWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
 
     mpCachePropWidget = new UBCachePropertiesWidget();
     mpCachePropWidget->registerMode(eUBDockPaletteWidget_BOARD);
-//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpCachePropWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
+//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpCachePropWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
 
     mpTeacherBarWidget = new UBTeacherBarWidget();
     mpTeacherBarWidget->registerMode(eUBDockPaletteWidget_BOARD);
-//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpTeacherBarWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
+//    connect(this, SIGNAL(signal_changeMode(eUBDockPaletteWidgetMode)), mpTeacherBarWidget, SLOT(slot_changeMode(eUBDockPaletteWidgetMode)));
 
     //------------------------------------------------//
     // Add the dock palettes
@@ -236,8 +241,8 @@ void UBBoardPaletteManager::slot_changeMainMode(UBApplicationController::MainMod
 void UBBoardPaletteManager::slot_changeDesktopMode(bool isDesktop)
 {
     UBApplicationController::MainMode currMode = UBApplication::applicationController->displayMode();
-    if(!isDesktop) 
-    {
+    if(!isDesktop) 
+    {
         switch( currMode )
         {
             case UBApplicationController::Board:
@@ -246,10 +251,10 @@ void UBBoardPaletteManager::slot_changeDesktopMode(bool isDesktop)
 
             default:
                 break;
-        }
-    }
+        }
+    }
     else
-        changeMode(eUBDockPaletteWidget_DESKTOP);
+        changeMode(eUBDockPaletteWidget_DESKTOP);
 }
 
 void UBBoardPaletteManager::setupPalettes()
@@ -899,4 +904,4 @@ void UBBoardPaletteManager::refreshPalettes()
 {
     mRightPalette->update();
     mLeftPalette->update();
-}
\ No newline at end of file
+}
diff --git a/src/board/UBBoardPaletteManager.h b/src/board/UBBoardPaletteManager.h
index 5b3ee587..a151bab0 100644
--- a/src/board/UBBoardPaletteManager.h
+++ b/src/board/UBBoardPaletteManager.h
@@ -26,7 +26,6 @@
 #include "gui/UBLibWidget.h"
 #include "gui/UBCachePropertiesWidget.h"
 #include "gui/UBTeacherBarWidget.h"
-
 #include "core/UBApplicationController.h"
 
 
diff --git a/src/core/UBApplicationController.cpp b/src/core/UBApplicationController.cpp
index b3560186..b239fa25 100644
--- a/src/core/UBApplicationController.cpp
+++ b/src/core/UBApplicationController.cpp
@@ -563,9 +563,7 @@ void UBApplicationController::downloadJsonFinished(QString currentJson)
     }
     else {
         if (isNoUpdateDisplayed) {
-            QMessageBox msgBox;
-            msgBox.setText (tr ("No update available"));
-            msgBox.exec();
+            mMainWindow->information(tr("Update"), tr("No update available"));
         }
     }
 }
diff --git a/src/core/UBPersistenceManager.cpp b/src/core/UBPersistenceManager.cpp
index 5e3449f5..8c2f3f95 100644
--- a/src/core/UBPersistenceManager.cpp
+++ b/src/core/UBPersistenceManager.cpp
@@ -14,6 +14,7 @@
  */
 
 #include "UBPersistenceManager.h"
+#include "gui/UBMainWindow.h"
 
 #include <QtXml>
 
@@ -1005,11 +1006,7 @@ void UBPersistenceManager::checkIfDocumentRepositoryExists()
         QString humanPath = QDir::cleanPath(mDocumentRepositoryPath);
         humanPath = QDir::toNativeSeparators(humanPath);
 
-        QMessageBox::question(
-            QApplication::activeWindow(),
-            tr("Document Repository Loss"),
-            tr("Sankore has lost access to the document repository '%1'. Unfortunately the application must shut down to avoid data corruption. Latest changes may be lost as well.").arg(humanPath),
-            QMessageBox::Yes);
+        UBApplication::mainWindow->warning(tr("Document Repository Loss"),tr("Sankore has lost access to the document repository '%1'. Unfortunately the application must shut down to avoid data corruption. Latest changes may be lost as well.").arg(humanPath));
 
         UBApplication::quit();
     }
diff --git a/src/core/UBPersistenceManager.h b/src/core/UBPersistenceManager.h
index 3c224f04..98a296f6 100644
--- a/src/core/UBPersistenceManager.h
+++ b/src/core/UBPersistenceManager.h
@@ -74,8 +74,8 @@ class UBPersistenceManager : public QObject
 
         virtual void persistDocumentScene(UBDocumentProxy* pDocumentProxy,
                 UBGraphicsScene* pScene, const int pSceneIndex);
-
         virtual void persistTeacherBar(UBDocumentProxy* pDocumentProxy, int page, sTeacherBarInfos infos);
+
         sTeacherBarInfos getTeacherBarInfos(UBDocumentProxy* pDocumentProxy, int page);
 
         virtual UBGraphicsScene* createDocumentSceneAt(UBDocumentProxy* pDocumentProxy, int index);
diff --git a/src/domain/UBGraphicsItemDelegate.cpp b/src/domain/UBGraphicsItemDelegate.cpp
index 00f1f200..ea5d792c 100644
--- a/src/domain/UBGraphicsItemDelegate.cpp
+++ b/src/domain/UBGraphicsItemDelegate.cpp
@@ -193,6 +193,7 @@ bool UBGraphicsItemDelegate::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
 
 bool UBGraphicsItemDelegate::weelEvent(QGraphicsSceneWheelEvent *event)
 {
+    Q_UNUSED(event);
     if( mDelegated->isSelected() )
     {
 //        event->accept();
diff --git a/src/gui/UBDocumentNavigator.cpp b/src/gui/UBDocumentNavigator.cpp
index 74bd3611..371cdbd5 100644
--- a/src/gui/UBDocumentNavigator.cpp
+++ b/src/gui/UBDocumentNavigator.cpp
@@ -141,7 +141,10 @@ void UBDocumentNavigator::updateSpecificThumbnail(int iPage)
     {
         // Save the current state of the scene
         pScene->setModified(true);
-        UBSvgSubsetAdaptor::persistScene(mCrntDoc,pScene, iPage);
+        if(UBApplication::boardController)
+        {
+            UBApplication::boardController->persistCurrentScene();
+        }
 
         UBThumbnailAdaptor::persistScene(mCrntDoc->persistencePath(), pScene, iPage);
 
diff --git a/src/gui/UBMainWindow.cpp b/src/gui/UBMainWindow.cpp
index 11d8b41c..1bc2cab5 100644
--- a/src/gui/UBMainWindow.cpp
+++ b/src/gui/UBMainWindow.cpp
@@ -16,7 +16,6 @@
 #include <QtGui>
 
 #include "UBMainWindow.h"
-
 #include "core/UBApplication.h"
 #include "core/UBApplicationController.h"
 #include "board/UBBoardController.h"
@@ -160,3 +159,26 @@ bool UBMainWindow::yesNoQuestion(QString windowTitle, QString text)
 
     return messageBox.clickedButton() == yesButton;
 }
+
+void UBMainWindow::oneButtonMessageBox(QString windowTitle, QString text, QMessageBox::Icon type)
+{
+    QMessageBox messageBox;
+    messageBox.setParent(this);
+    messageBox.setWindowFlags(Qt::Dialog);
+    messageBox.setWindowTitle(windowTitle);
+    messageBox.setText(text);
+    messageBox.addButton(tr("Ok"),QMessageBox::YesRole);
+    messageBox.setIcon(type);
+    messageBox.exec();
+}
+
+void UBMainWindow::warning(QString windowTitle, QString text)
+{
+    oneButtonMessageBox(windowTitle,text, QMessageBox::Warning);
+}
+
+void UBMainWindow::information(QString windowTitle, QString text)
+{
+    oneButtonMessageBox(windowTitle, text, QMessageBox::Information);
+}
+
diff --git a/src/gui/UBMainWindow.h b/src/gui/UBMainWindow.h
index 2bd6fc25..4150bbec 100644
--- a/src/gui/UBMainWindow.h
+++ b/src/gui/UBMainWindow.h
@@ -20,6 +20,7 @@
 #include <QMainWindow>
 #include <QWidget>
 #include <QWebView>
+#include <QMessageBox>
 
 class QStackedLayout;
 
@@ -41,7 +42,10 @@ class UBMainWindow : public QMainWindow, public Ui::MainWindow
 
         void addDocumentsWidget(QWidget *pWidget);
         void switchToDocumentsWidget();
+
         bool yesNoQuestion(QString windowTitle, QString text);
+        void warning(QString windowTitle, QString text);
+        void information(QString windowTitle, QString text);
 
     signals:
         void closeEvent_Signal( QCloseEvent *event );
@@ -50,6 +54,7 @@ class UBMainWindow : public QMainWindow, public Ui::MainWindow
         void onExportDone();
 
     protected:
+        void oneButtonMessageBox(QString windowTitle, QString text, QMessageBox::Icon type);
 
         virtual void keyPressEvent(QKeyEvent *event);
         virtual void closeEvent (QCloseEvent *event);
diff --git a/src/gui/UBUpdateDlg.cpp b/src/gui/UBUpdateDlg.cpp
index 2c2ba56b..c0651258 100644
--- a/src/gui/UBUpdateDlg.cpp
+++ b/src/gui/UBUpdateDlg.cpp
@@ -12,28 +12,29 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#include <QMessageBox>
 #include <QFileDialog>
 
 #include "UBUpdateDlg.h"
+#include "core/UBApplication.h"
+#include "UBMainWindow.h"
 
 #include "core/memcheck.h"
 
 UBUpdateDlg::UBUpdateDlg(QWidget *parent, int nbFiles, const QString& bkpPath)
-        : QDialog(parent)
-        , mMainLayout(NULL)
-        , mNbFilesLabel(NULL)
-        , mBkpLabel(NULL)
-        , mBkpPath(NULL)
-        , mBrowseBttn(NULL)
-        , mpDlgBttn(NULL)
-        , mLayout(NULL)
-        , mHLayout(NULL)
-        , mStackedWidget(NULL)
-        , mDialogWidget(NULL)
-        , mProgressWidget(NULL)
-        , mProgressLayout(NULL)
-        , mProgressLabel(NULL)
+    : QDialog(parent)
+    , mMainLayout(NULL)
+    , mNbFilesLabel(NULL)
+    , mBkpLabel(NULL)
+    , mBkpPath(NULL)
+    , mBrowseBttn(NULL)
+    , mpDlgBttn(NULL)
+    , mLayout(NULL)
+    , mHLayout(NULL)
+    , mStackedWidget(NULL)
+    , mDialogWidget(NULL)
+    , mProgressWidget(NULL)
+    , mProgressLayout(NULL)
+    , mProgressLabel(NULL)
 
 {
     mDialogWidget = new QWidget(this);
@@ -178,18 +179,16 @@ void UBUpdateDlg::onUpdate()
 
 void UBUpdateDlg::onFilesUpdated(bool bResult)
 {
-	this->hide();
+    this->hide();
     QString qsMsg;
 
-    if (bResult)
-    {
+    if (bResult) {
         qsMsg = tr("Files update successful!\nPlease reboot the application to access the updated documents.");
     }
-    else
-    {
+    else {
         qsMsg = tr("An error occured during the update. The files have not been affected.");
     }
-    QMessageBox::information(this, tr("Files update results"), qsMsg, QMessageBox::Ok);
+    UBApplication::mainWindow->information(tr("Files update results"), qsMsg);
 }
 
 QString UBUpdateDlg::backupPath()
diff --git a/src/network/UBNetworkAccessManager.cpp b/src/network/UBNetworkAccessManager.cpp
index 6529c388..c2b7aa10 100644
--- a/src/network/UBNetworkAccessManager.cpp
+++ b/src/network/UBNetworkAccessManager.cpp
@@ -160,14 +160,18 @@ void UBNetworkAccessManager::sslErrors(QNetworkReply *reply, const QList<QSslErr
 
         QString errors = errorStrings.join(QLatin1String("\n"));
 
-        int ret = QMessageBox::warning(mainWindow, QCoreApplication::applicationName(),
-                tr("SSL Errors:\n\n%1\n\n%2\n\n"
-                        "Do you want to ignore these errors for this host?").arg(reply->url().toString()).arg(errors),
-                        QMessageBox::Yes | QMessageBox::No,
-                        QMessageBox::No);
-
-        if (ret == QMessageBox::Yes)
-        {
+        QMessageBox messageBox;
+        messageBox.setParent(mainWindow);
+        messageBox.setWindowFlags(Qt::Dialog);
+        messageBox.setWindowTitle(QCoreApplication::applicationName());
+        messageBox.setText(tr("SSL Errors:\n\n%1\n\n%2\n\n"
+                              "Do you want to ignore these errors for this host?").arg(reply->url().toString()).arg(errors));
+        QPushButton* yesButton = messageBox.addButton(tr("Yes"),QMessageBox::YesRole);
+        messageBox.addButton(tr("No"),QMessageBox::NoRole);
+        messageBox.setIcon(QMessageBox::Question);
+        messageBox.exec();
+
+        if(messageBox.clickedButton() == yesButton) {
             reply->ignoreSslErrors();
             sslTrustedHostList.append(replyHost);
         }
diff --git a/src/web/browser/WBWebView.cpp b/src/web/browser/WBWebView.cpp
index 23fb6cb5..eb0be66f 100644
--- a/src/web/browser/WBWebView.cpp
+++ b/src/web/browser/WBWebView.cpp
@@ -168,8 +168,7 @@ void WBWebPage::handleUnsupportedContent(QNetworkReply *reply)
         messageBox.setText(tr("Download PDF Document: would you prefer to download the PDF file or add it to the current Sankore document?"));
 
         messageBox.addButton(tr("Download"), QMessageBox::AcceptRole);
-        QAbstractButton *addButton =
-            messageBox.addButton(tr("Add to Current Document"), QMessageBox::AcceptRole);
+        QAbstractButton *addButton = messageBox.addButton(tr("Add to Current Document"), QMessageBox::AcceptRole);
 
         messageBox.exec();
         if (messageBox.clickedButton() == addButton)