diff --git a/crlcore/etc/common/display.conf b/crlcore/etc/common/display.conf
index 7d04738d..9e9ace2d 100644
--- a/crlcore/etc/common/display.conf
+++ b/crlcore/etc/common/display.conf
@@ -8,7 +8,7 @@ else:
     poly2Color = 'Orange'
 
 
-defaultStyle = 'Printer.Coriolis'
+defaultStyle = 'Alliance.Classic [black]'
 
 stylesTable = \
     ( ( (Style    , 'Alliance.Coriolis [black]', 'Alliance Coriolis Look - black background')
diff --git a/hurricane/src/hurricane/Cell.cpp b/hurricane/src/hurricane/Cell.cpp
index 08c4b6b5..06ee8db2 100644
--- a/hurricane/src/hurricane/Cell.cpp
+++ b/hurricane/src/hurricane/Cell.cpp
@@ -936,15 +936,18 @@ void Cell::_preDestroy()
     _slaveEntityMap.begin()->second->destroy();
   }
 
-//for ( View*     view          : getViews()          ) view->setCell( NULL );
-  for ( Marker*   marker        : getMarkers()        ) marker->destroy();
-  for ( Instance* slaveInstance : getSlaveInstances() ) slaveInstance->destroy();
-  for ( Instance* instance      : getInstances()      ) instance->destroy();
-  for ( Net*      net           : getNets() ) {
+  Markers   markers   = getMarkers       (); while ( markers  .getFirst() ) markers  .getFirst()->destroy();
+  Instances instances = getSlaveInstances(); while ( instances.getFirst() ) instances.getFirst()->destroy();
+            instances = getInstances     (); while ( instances.getFirst() ) instances.getFirst()->destroy();
+
+  Nets nets = getNets();
+  while ( nets.getFirst() ) {
+    Net* net = nets.getFirst();
     net->_getMainName().detachAll();
     net->destroy();
   }
-  for ( auto   islave : _netAliasSet ) delete islave;
+  for ( auto islave : _netAliasSet ) delete islave;
+
   for ( Slice* slice  : getSlices()  ) slice->_destroy();
   while ( not _extensionSlices.empty() ) _removeSlice( _extensionSlices.begin()->second );
 
diff --git a/hurricane/src/isobar/hurricane/isobar/PyHurricane.h b/hurricane/src/isobar/hurricane/isobar/PyHurricane.h
index 51d590a0..c4f105fe 100644
--- a/hurricane/src/isobar/hurricane/isobar/PyHurricane.h
+++ b/hurricane/src/isobar/hurricane/isobar/PyHurricane.h
@@ -1399,16 +1399,16 @@ extern "C" {
 
 # define   HCATCH  \
     }                                                            \
-    catch ( Warning& w ) {                                       \
+    catch ( const Warning& w ) {                                 \
       std::string message = "\n" + getString(w);                 \
       PyErr_Warn ( HurricaneWarning, const_cast<char*>(message.c_str()) ); \
     }                                                            \
-    catch ( Error& e ) {                                         \
+    catch ( const Error& e ) {                                   \
       std::string message = "\n" + getString(e);                 \
       PyErr_SetString ( HurricaneError, message.c_str() );       \
       return NULL;                                               \
     }                                                            \
-    catch ( std::exception& e )  {                               \
+    catch ( const std::exception& e )  {                         \
       std::string message = "\n" + std::string(e.what());        \
       PyErr_SetString ( HurricaneError, message.c_str() );       \
       return NULL;                                               \