catched exception
diff --git a/org.eclipse.opencert.chess.argumentGenerator/src/org/eclipse/opencert/chess/argumentGenerator/argumentation/DawnArgDiagramUtil.java b/org.eclipse.opencert.chess.argumentGenerator/src/org/eclipse/opencert/chess/argumentGenerator/argumentation/DawnArgDiagramUtil.java
index 5f9a089..a446ece 100644
--- a/org.eclipse.opencert.chess.argumentGenerator/src/org/eclipse/opencert/chess/argumentGenerator/argumentation/DawnArgDiagramUtil.java
+++ b/org.eclipse.opencert.chess.argumentGenerator/src/org/eclipse/opencert/chess/argumentGenerator/argumentation/DawnArgDiagramUtil.java
@@ -124,9 +124,13 @@
 					editp.installEditPolicy(EditPolicyRoles.CANONICAL_ROLE,

 							new CasePersistedCanonicalEditPolicy()); //MCP OJO: para evitar bucle infinito

 					*/

+					try{

 					

  					editp.installEditPolicy(EditPolicyRoles.CANONICAL_ROLE,

 							new DawnCasePersistedCanonicalEditPolicy());

+					}catch (Exception ex){

+						ex.printStackTrace();

+					}

  					

 	        		// No puedo cerrar el diagrama porque no se crean las views!!! y pierdo la perspectiva

 	        		DawnArgDiagramEditor dawnEditorPart = (DawnArgDiagramEditor)editorPart;