diff --git a/src/ui/GTURTLEModeling.java b/src/ui/GTURTLEModeling.java
index 9dcdf8727805343c281f4de61903c0e49b18c9ff..4c9567f8933eb7f6ce95022f30629dfcc9e526a7 100755
--- a/src/ui/GTURTLEModeling.java
+++ b/src/ui/GTURTLEModeling.java
@@ -1120,7 +1120,7 @@ public class GTURTLEModeling {
               }
 			}
 		} catch (Exception e) {
-			System.out.println("Exception " + e.getMessage());
+			System.out.println("Exception during projection" + e.getMessage());
 			return null;
 		}
 		return new String(result);
@@ -1231,7 +1231,7 @@ public class GTURTLEModeling {
 				}
 			}
 		} catch (Exception e) {
-			System.out.println("Exception " + e.getMessage());
+			System.out.println("Exception convert0" + e.getMessage());
 			return null;
 		}
 		return new String(result);
@@ -1335,7 +1335,7 @@ public class GTURTLEModeling {
                 }
             }
         } catch (Exception e) {
-            System.out.println("Exception " + e.getMessage());
+            System.out.println("Exception09545 " + e.getMessage());
             return null;
         }
         return new String(result);
diff --git a/src/ui/interactivesimulation/JFrameInteractiveSimulation.java b/src/ui/interactivesimulation/JFrameInteractiveSimulation.java
index c76a4a56c17c6868b93043ee1a90aea2ab277643..b044f73777eb37db5e45084157aba3c79b38907c 100755
--- a/src/ui/interactivesimulation/JFrameInteractiveSimulation.java
+++ b/src/ui/interactivesimulation/JFrameInteractiveSimulation.java
@@ -1106,6 +1106,9 @@ public	class JFrameInteractiveSimulation extends JFrame implements ActionListene
 	
 	protected boolean loadConfiguration(Node node1) {
 		NodeList diagramNl = node1.getChildNodes();
+		if (diagramN == null) {
+			return false;
+		}
 		Element elt, elt0;
 		Node node, node0;
 		NodeList nl;
@@ -1135,6 +1138,11 @@ public	class JFrameInteractiveSimulation extends JFrame implements ActionListene
 			for(int j=0; j<diagramNl.getLength(); j++) {
 				//System.out.println("Ndes: " + j);
 				node = diagramNl.item(j);
+				
+				if (node == null) {
+					return false;
+				}
+				
 				if (node.getNodeType() == Node.ELEMENT_NODE) {
 					elt = (Element)node;
 					
@@ -1310,7 +1318,7 @@ public	class JFrameInteractiveSimulation extends JFrame implements ActionListene
 				}
 			}
 		} catch (Exception e) {
-			System.err.println("Exception " + e.getMessage());
+			System.err.println("Exception in xml parsing " + e.getMessage() + " node= " + node1);
 			return false;
 		}
 		
diff --git a/src/ui/window/StatisticsTableModel.java b/src/ui/window/StatisticsTableModel.java
index d1bbe7a13a9b80ec1b79ee67256a9af7e57711a0..a0e8b5877a312d85fd46699ebbdd86fe6b3b2576 100755
--- a/src/ui/window/StatisticsTableModel.java
+++ b/src/ui/window/StatisticsTableModel.java
@@ -151,7 +151,7 @@ public class StatisticsTableModel extends AbstractTableModel implements SteppedA
 
 			}
 		} catch (Exception e) {
-			System.out.println("Exception " + e.getMessage());
+			System.out.println("Exception stm0" + e.getMessage());
 		}
 		Collections.sort(statisticData);
 	}
@@ -194,7 +194,7 @@ public class StatisticsTableModel extends AbstractTableModel implements SteppedA
 
 			}
 		} catch (Exception e) {
-			System.out.println("Exception " + e.getMessage());
+			System.out.println("Exception stm1" + e.getMessage());
 		}
 		Collections.sort(statisticData);
 	}