diff --git a/resources/etc/Tutorial/tutorial_en/index.html b/resources/etc/Tutorial/tutorial_en/index.html
index 014d6229..c47a787d 100644
--- a/resources/etc/Tutorial/tutorial_en/index.html
+++ b/resources/etc/Tutorial/tutorial_en/index.html
@@ -45,7 +45,7 @@ body {
 <div class="g200">
 
 <a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/User+manual+EN+2.00" target="_blank"><img src="images/manuel.png" style="width: 188px; border: 1px solid #999"/></a>
-<br/><br/><a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/Le+manuel+qui+manquait" target="_blank">
+<br/><br/><a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/User+manual+EN+2.00" target="_blank">
 <h5 style="text-align: center;">The user manual</h5></a>
 
 </div>
diff --git a/resources/etc/Tutorial/tutorial_fr/index.html b/resources/etc/Tutorial/tutorial_fr/index.html
index b644c48a..66467cf7 100644
--- a/resources/etc/Tutorial/tutorial_fr/index.html
+++ b/resources/etc/Tutorial/tutorial_fr/index.html
@@ -45,7 +45,7 @@ body {
 <div class="g200">
 
 <a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/Le+manuel+du+logiciel+FR+2.00" target="_blank"><img src="images/manuel.png" style="width: 188px; border: 1px solid #999"/></a>
-<br/><br/><a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/Le+manuel+qui+manquait" target="_blank">
+<br/><br/><a href="http://planete.sankore.org/xwiki/bin/view/Pedagogique/Le+manuel+du+logiciel+FR+2.00" target="_blank">
 <h5 style="text-align: center;">Le manuel d'utilisation</h5></a>
 
 </div>
diff --git a/src/adaptors/UBSvgSubsetAdaptor.cpp b/src/adaptors/UBSvgSubsetAdaptor.cpp
index de43189f..5435b8e9 100644
--- a/src/adaptors/UBSvgSubsetAdaptor.cpp
+++ b/src/adaptors/UBSvgSubsetAdaptor.cpp
@@ -1025,6 +1025,8 @@ UBGraphicsGroupContainerItem* UBSvgSubsetAdaptor::UBSvgSubsetReader::readGroup()
                 UBGraphicsGroupContainerItem *curGroup = readGroup();
                 if (curGroup)
                     groupContainer.append(curGroup);
+                else
+                    qDebug() << "this is an error";
             }
             else if (mXmlReader.name() == tElement)
             {
@@ -1042,7 +1044,10 @@ UBGraphicsGroupContainerItem* UBSvgSubsetAdaptor::UBSvgSubsetReader::readGroup()
                 }
                 else // item
                 {
-                    groupContainer.append(curItem);
+                    if(curItem)
+                        groupContainer.append(curItem);
+                    else
+                        qDebug() << "this is an error";
                 }
             }else {
                 mXmlReader.skipCurrentElement();
@@ -1078,7 +1083,10 @@ UBGraphicsGroupContainerItem* UBSvgSubsetAdaptor::UBSvgSubsetReader::readGroup()
         if (pStrokesGroup)
         {
             QGraphicsItem *strokeGroup = qgraphicsitem_cast<QGraphicsItem *>(pStrokesGroup);
-            groupContainer.append(strokeGroup);
+            if(strokeGroup)
+                groupContainer.append(strokeGroup);
+            else
+                qDebug() << "this is an error";
         }
     }
 
@@ -1126,6 +1134,9 @@ QGraphicsItem *UBSvgSubsetAdaptor::UBSvgSubsetReader::readElementFromGroup()
     QString uuid = id.right(QUuid().toString().size());
     result = mScene->itemForUuid(QUuid(uuid));
 
+    if(!result)
+        qDebug() << "uuid " << uuid;
+
     mXmlReader.skipCurrentElement();
     mXmlReader.readNext();