diff --git a/Icarus/FilledSolidPanel/FilledSolidPanelVM.vb b/Icarus/FilledSolidPanel/FilledSolidPanelVM.vb
index 069a3f2..5c53a33 100644
--- a/Icarus/FilledSolidPanel/FilledSolidPanelVM.vb
+++ b/Icarus/FilledSolidPanel/FilledSolidPanelVM.vb
@@ -353,8 +353,8 @@ Public Class FilledSolidPanelVM
             NotifyPropertyChanged(NameOf(bRotate_IsChecked))
             Map.refRightPanelVM.SetSelPanel(RightPanelVM.Panels.AUXSOLIDPARAM)
             NotifyPropertyChanged(NameOf(FilledSolidList_IsEnabled))
-            ' disattivo lista filled solid
-            SetFilledSolidListIsEnabled(False)
+            ' disattivo interfaccia
+            ManageInterface(False)
          Else
             NotifyPropertyChanged(NameOf(m_bMachParam_IsChecked))
          End If
@@ -364,6 +364,8 @@ Public Class FilledSolidPanelVM
       m_bMachParam_IsChecked = False
       NotifyPropertyChanged(NameOf(bMachParam_IsChecked))
       NotifyPropertyChanged(NameOf(FilledSolidList_IsEnabled))
+      ' riattivo interfaccia
+      ManageInterface(True)
    End Sub
 
    Public ReadOnly Property Compo_Visibility As Visibility
@@ -622,8 +624,13 @@ Public Class FilledSolidPanelVM
             EgtSelectObj(m_SelFilledSolid.nCurveId)
          Case FilledSolidSelectionTypes.EXTRUSION
             ' creo layer per estrusione
-            Dim nNewExtrusionLayerId As Integer = EgtCreateGroup(m_nPartId)
-            EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Dim nNewExtrusionLayerId As Integer = EgtGetFirstNameInGroup(m_nPartId, LAY_NEWEXTRUSION)
+            If nNewExtrusionLayerId = GDB_ID.NULL Then
+               nNewExtrusionLayerId = EgtCreateGroup(m_nPartId)
+               EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Else
+               EgtEmptyGroup(nNewExtrusionLayerId)
+            End If
             EgtSetCurrPartLayer(m_nPartId, nNewExtrusionLayerId)
             EgtSelectObj(m_SelFilledSolid.nCurveId)
          Case FilledSolidSelectionTypes.BOTH
@@ -1219,6 +1226,7 @@ Public Class FilledSolidPanelVM
    ''' </summary>
    Public Sub CPlaneElevation(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ELEVATION)
    End Sub
 
@@ -1243,6 +1251,7 @@ Public Class FilledSolidPanelVM
    ''' </summary>
    Public Sub CPlaneOrigin(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ORIGIN)
    End Sub
 
diff --git a/Icarus/RibPanel/RibPanelVM.vb b/Icarus/RibPanel/RibPanelVM.vb
index 62a790b..cf6896c 100644
--- a/Icarus/RibPanel/RibPanelVM.vb
+++ b/Icarus/RibPanel/RibPanelVM.vb
@@ -378,8 +378,8 @@ Public Class RibPanelVM
             NotifyPropertyChanged(NameOf(bRotate_IsChecked))
             Map.refRightPanelVM.SetSelPanel(RightPanelVM.Panels.RIBPARAM)
             NotifyPropertyChanged(NameOf(RibList_IsEnabled))
-            ' disattivo lista ribs
-            SetRibListIsEnabled(False)
+            ' disattivo interfaccia
+            ManageInterface(False)
          Else
             NotifyPropertyChanged(NameOf(m_bMachParam_IsChecked))
          End If
@@ -389,6 +389,8 @@ Public Class RibPanelVM
       m_bMachParam_IsChecked = False
       NotifyPropertyChanged(NameOf(bMachParam_IsChecked))
       NotifyPropertyChanged(NameOf(RibList_IsEnabled))
+      ' riattivo interfaccia
+      ManageInterface(True)
    End Sub
 
    Public ReadOnly Property Compo_Visibility As Visibility
@@ -647,8 +649,13 @@ Public Class RibPanelVM
             EgtSelectObj(m_SelRib.nCurveId)
          Case RibSelectionTypes.EXTRUSION
             ' creo layer per estrusione
-            Dim nNewExtrusionLayerId As Integer = EgtCreateGroup(m_nPartId)
-            EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Dim nNewExtrusionLayerId As Integer = EgtGetFirstNameInGroup(m_nPartId, LAY_NEWEXTRUSION)
+            If nNewExtrusionLayerId = GDB_ID.NULL Then
+               nNewExtrusionLayerId = EgtCreateGroup(m_nPartId)
+               EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Else
+               EgtEmptyGroup(nNewExtrusionLayerId)
+            End If
             EgtSetCurrPartLayer(m_nPartId, nNewExtrusionLayerId)
             EgtSelectObj(m_SelRib.nCurveId)
          Case RibSelectionTypes.BOTH
@@ -950,7 +957,7 @@ Public Class RibPanelVM
          Else
             SelRib = Nothing
             m_bEdit_IsChecked = False
-            NotifyPropertyChanged(NameOf( bEdit_IsChecked))
+            NotifyPropertyChanged(NameOf(bEdit_IsChecked))
          End If
          NotifyPropertyChanged(NameOf(SelRib))
       End If
@@ -1238,6 +1245,7 @@ Public Class RibPanelVM
    ''' </summary>
    Public Sub CPlaneElevation(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ELEVATION)
    End Sub
 
@@ -1262,6 +1270,7 @@ Public Class RibPanelVM
    ''' </summary>
    Public Sub CPlaneOrigin(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ORIGIN)
    End Sub
 
diff --git a/Icarus/ShellNumberPanel/ShellNumberPanelVM.vb b/Icarus/ShellNumberPanel/ShellNumberPanelVM.vb
index c374ea7..05d22ba 100644
--- a/Icarus/ShellNumberPanel/ShellNumberPanelVM.vb
+++ b/Icarus/ShellNumberPanel/ShellNumberPanelVM.vb
@@ -358,8 +358,8 @@ Public Class ShellNumberPanelVM
             NotifyPropertyChanged(NameOf(bRotate_IsChecked))
             Map.refRightPanelVM.SetSelPanel(RightPanelVM.Panels.SHELLNUMBERPARAM)
             NotifyPropertyChanged(NameOf(ShellNumberList_IsEnabled))
-            ' disattivo lista shell number
-            SetShellNumberListIsEnabled(False)
+            ' disattivo interfaccia
+            ManageInterface(False)
          Else
             NotifyPropertyChanged(NameOf(m_bMachParam_IsChecked))
          End If
@@ -369,6 +369,8 @@ Public Class ShellNumberPanelVM
       m_bMachParam_IsChecked = False
       NotifyPropertyChanged(NameOf(bMachParam_IsChecked))
       NotifyPropertyChanged(NameOf(ShellNumberList_IsEnabled))
+      ' riattivo interfaccia
+      ManageInterface(True)
    End Sub
 
    Public ReadOnly Property Compo_Visibility As Visibility
@@ -627,8 +629,13 @@ Public Class ShellNumberPanelVM
             EgtSelectObj(m_SelShellNumber.nCurveId)
          Case ShellNumberSelectionTypes.EXTRUSION
             ' creo layer per estrusione
-            Dim nNewExtrusionLayerId As Integer = EgtCreateGroup(m_nPartId)
-            EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Dim nNewExtrusionLayerId As Integer = EgtGetFirstNameInGroup(m_nPartId, LAY_NEWEXTRUSION)
+            If nNewExtrusionLayerId = GDB_ID.NULL Then
+               nNewExtrusionLayerId = EgtCreateGroup(m_nPartId)
+               EgtSetName(nNewExtrusionLayerId, LAY_NEWEXTRUSION)
+            Else
+               EgtEmptyGroup(nNewExtrusionLayerId)
+            End If
             EgtSetCurrPartLayer(m_nPartId, nNewExtrusionLayerId)
             EgtSelectObj(m_SelShellNumber.nCurveId)
          Case ShellNumberSelectionTypes.BOTH
@@ -1225,6 +1232,7 @@ Public Class ShellNumberPanelVM
    ''' </summary>
    Public Sub CPlaneElevation(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ELEVATION)
    End Sub
 
@@ -1249,6 +1257,7 @@ Public Class ShellNumberPanelVM
    ''' </summary>
    Public Sub CPlaneOrigin(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ORIGIN)
    End Sub
 
diff --git a/Icarus/StartMachPanel/StartMachPanelVM.vb b/Icarus/StartMachPanel/StartMachPanelVM.vb
index 387ccc0..7b97fb2 100644
--- a/Icarus/StartMachPanel/StartMachPanelVM.vb
+++ b/Icarus/StartMachPanel/StartMachPanelVM.vb
@@ -928,6 +928,7 @@ Public Class StartMachPanelVM
    ''' </summary>
    Public Sub CPlaneElevation(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ELEVATION)
    End Sub
 
@@ -952,6 +953,7 @@ Public Class StartMachPanelVM
    ''' </summary>
    Public Sub CPlaneOrigin(ByVal param As Object)
       If Map.refSceneHostVM.MainController.GetStep <> 0 OrElse m_bCPlaneObj_IsActive Then Return
+      ManageInterface(False)
       Map.refSceneHostVM.MainController.ExecuteCommand(Controller.CMD.GRID_ORIGIN)
    End Sub