diff --git a/Icarus/Icarus.vbproj b/Icarus/Icarus.vbproj
index 9c26b16..6dae7de 100644
--- a/Icarus/Icarus.vbproj
+++ b/Icarus/Icarus.vbproj
@@ -265,6 +265,7 @@
     </Compile>
     <Compile Include="Utility\DisableModifiedMgr.vb" />
     <Compile Include="Utility\EgwCrypto.vb" />
+    <Compile Include="Utility\GeomEntityColors.vb" />
     <Compile Include="Utility\LuaExec.vb" />
     <Compile Include="Utility\Map.vb" />
     <Compile Include="Utility\MyMachine.vb" />
diff --git a/Icarus/ImportPanel/ImportPanelVM.vb b/Icarus/ImportPanel/ImportPanelVM.vb
index 0a40424..fedd54f 100644
--- a/Icarus/ImportPanel/ImportPanelVM.vb
+++ b/Icarus/ImportPanel/ImportPanelVM.vb
@@ -224,7 +224,8 @@ Public Class ImportPanelVM
          Return
       Else
          ' Creo pezzi e layer necessari
-         For Each ImportPart In m_ImportPartList
+         For ImportPartIndex = 0 To m_ImportPartList.Count - 1
+            Dim ImportPart As ImportPart = m_ImportPartList(ImportPartIndex)
             Dim frImportedPart As New Frame3d
             EgtGetGroupGlobFrame(m_nImportedPartId, frImportedPart)
             Dim nPartId As Integer = EgtCreateGroup(GDB_ID.ROOT, frImportedPart)
@@ -328,6 +329,20 @@ Public Class ImportPanelVM
                      For Each GeomEntity In ImportLayer.EntityList
                         EgtRelocateGlob(GeomEntity.nId, nOthersLayerId, GDB_POS.LAST_SON)
                      Next
+                     If ImportPartIndex = 0 Then
+                        For Each GeomEntity In ImportedEntityList
+                           ' se curva
+                           Dim EntityType As GDB_TY = EgtGetType(GeomEntity.nId)
+                           Select Case EntityType
+                              Case GDB_TY.CRV_ARC, GDB_TY.CRV_BEZ, GDB_TY.CRV_LINE
+                                 '  la trasformo in curva compo
+                                 EgtCreateCurveCompo(nOthersLayerId, GeomEntity.nId, True)
+                              Case Else
+                                 ' altrimenti la sposto solamente
+                                 EgtRelocateGlob(GeomEntity.nId, nOthersLayerId, GDB_POS.LAST_SON)
+                           End Select
+                        Next
+                     End If
                End Select
             Next
             ' aggiungo riferimento
@@ -366,7 +381,7 @@ Public Class ImportPanelVM
             End If
             EgtSetInfo(nReferenceLayerId, KEY_REFERENCE, PrintSolidEntity.Reference)
             ' appoggio il pezzo sulla tavola
-            EgtMove( nPartId, New Vector3d(0, 0, -b3PrintSolid.Min.z))
+            EgtMove(nPartId, New Vector3d(0, 0, -b3PrintSolid.Min.z))
             ' lo aggiungo a lista pezzi 
             Dim sFilePath As String = ""
             EgtGetInfo(m_nImportedPartId, FILE_PATH, sFilePath)
diff --git a/Icarus/ModifyPartPanel/ModifyPartPanelV.xaml b/Icarus/ModifyPartPanel/ModifyPartPanelV.xaml
index e1368ae..5709294 100644
--- a/Icarus/ModifyPartPanel/ModifyPartPanelV.xaml
+++ b/Icarus/ModifyPartPanel/ModifyPartPanelV.xaml
@@ -60,11 +60,22 @@
                   <TextBlock Text="{Binding ghReference, UpdateSourceTrigger=PropertyChanged}"/>
                </StackPanel>
             </HierarchicalDataTemplate>
+            <!-- Menu' tasto destro -->
+            <ContextMenu x:Key="RowMenu" ItemsSource="{Binding MenuList}" >
+               <ContextMenu.ItemContainerStyle>
+                  <Style TargetType="MenuItem">
+                     <Setter Property="Command" Value="{Binding MenuItem_Command}"/>
+                     <Setter Property="CommandParameter" Value="{Binding MenuItem_Command}"/>
+                     <Setter Property="Header" Value="{Binding sMsg}"/>
+                  </Style>
+               </ContextMenu.ItemContainerStyle>
+            </ContextMenu>
          </TreeView.Resources>
          <TreeView.ItemContainerStyle>
             <Style TargetType="{x:Type TreeViewItem}">
                <Setter Property="IsSelected" Value="{Binding bIsSelected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
                <Setter Property="IsExpanded" Value="True" />
+               <Setter Property="ContextMenu" Value="{StaticResource RowMenu}" />
             </Style>
          </TreeView.ItemContainerStyle>
       </TreeView>
diff --git a/Icarus/ModifyPartPanel/ModifyPartUtility.vb b/Icarus/ModifyPartPanel/ModifyPartUtility.vb
index fbfa7fa..3d522c6 100644
--- a/Icarus/ModifyPartPanel/ModifyPartUtility.vb
+++ b/Icarus/ModifyPartPanel/ModifyPartUtility.vb
@@ -5,6 +5,14 @@ Imports EgtWPFLib5
 Public Class ModifyEntity
    Inherits VMBase
 
+   ' layer sotto cui e' questa entita'
+   Private m_OrigLayer As ModifyLayer
+   Friend ReadOnly Property OrigLayer As ModifyLayer
+      Get
+         Return m_OrigLayer
+      End Get
+   End Property
+
    Private m_bIsSelected As Boolean
    Public Property bIsSelected As Boolean
       Get
@@ -39,41 +47,57 @@ Public Class ModifyEntity
 
    Public ReadOnly Property ghName As String
       Get
-         Return m_nId & If(Not String.IsNullOrWhiteSpace(m_sName), " - " & m_sName, "")
+         Return m_nId
       End Get
    End Property
 
-   ' Definizione comandi
-   Private m_cmdImportedEntity As ICommand
+   Private m_MenuList As New List(Of MenuItemVm)
+   Public Property MenuList As List(Of MenuItemVm)
+      Get
+         Return m_MenuList
+      End Get
+      Set(value As List(Of MenuItemVm))
+         m_MenuList = value
+      End Set
+   End Property
 
-   Sub New(nId As Integer, sName As String)
+   Sub New(nId As Integer, sName As String, OrigLayer As ModifyLayer)
       m_nId = nId
       m_sName = sName
+      m_OrigLayer = OrigLayer
+      ' aggiungo voci layer a contextmenu
+      CreateContextMenu(OrigLayer)
    End Sub
 
-#Region "COMMANDS"
-
-#Region "ImportedEntity"
-
-   Public ReadOnly Property ImportedEntity_DoubleClick As ICommand
-      Get
-         If m_cmdImportedEntity Is Nothing Then
-            m_cmdImportedEntity = New Command(AddressOf ImportedEntity)
-         End If
-         Return m_cmdImportedEntity
-      End Get
-   End Property
-
-   Public Sub ImportedEntity()
-      If Not IsNothing(Map.refImportPanelVM.SelImportLayer) Then
-         'Map.refModifyPartPanelVM.ImportedEntityList.Remove(Me)
-         Map.refModifyPartPanelVM.SelModifyLayer.EntityList.Add(Me)
-      End If
+   Friend Sub UpdateContextMenu(OrigLayer As ModifyLayer)
+      m_MenuList.Clear()
+      ' aggiungo voci layer a contextmenu
+      CreateContextMenu(OrigLayer)
    End Sub
 
-#End Region    ' ImportedEntity
+   Friend Sub CreateContextMenu(OrigLayer As ModifyLayer)
+      For Each ProjectPart In Map.refTopPanelVM.PartList
+         ' verifico in quali layer puo' andare questo elemento
+         Dim EntityType As GDB_TY = EgtGetType(nId)
+         Select Case EntityType
+            Case GDB_TY.GEO_POINT, GDB_TY.CRV_COMPO, GDB_TY.CRV_ARC, GDB_TY.CRV_BEZ, GDB_TY.CRV_LINE
+               ' recupero i layer
+               If OrigLayer.Type <> ModifyLayer.LayerType.MACH_START Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.MACH_START, ProjectPart))
+               If OrigLayer.Type <> ModifyLayer.LayerType.OTHERS Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.OTHERS, ProjectPart))
+            Case GDB_TY.SRF_MESH
+               ' verifico se volume chiuso
+               If OrigLayer.Type <> ModifyLayer.LayerType.PRINT_SOLID Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.PRINT_SOLID, ProjectPart))
+               If OrigLayer.Type <> ModifyLayer.LayerType.SHELL_NUMBER Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.SHELL_NUMBER, ProjectPart))
+               If OrigLayer.Type <> ModifyLayer.LayerType.AUX_SOLIDS Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.AUX_SOLIDS, ProjectPart))
+               If OrigLayer.Type <> ModifyLayer.LayerType.RIBS Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.RIBS, ProjectPart))
+               If OrigLayer.Type <> ModifyLayer.LayerType.OTHERS Then m_MenuList.Add(New MenuItemVm(Me, OrigLayer, ModifyLayer.LayerType.OTHERS, ProjectPart))
+         End Select
+      Next
+   End Sub
 
-#End Region    ' COMMANDS
+   Friend Sub UpdateOrigLayer(NewLayer As ModifyLayer)
+      m_OrigLayer = NewLayer
+   End Sub
 
 End Class
 
@@ -91,10 +115,10 @@ Public Class ModifyPart
       End Set
    End Property
 
-   Private m_nId As Integer
-   Public ReadOnly Property nId As Integer
+   Private m_PrintPart As Print3dPartVM
+   Public ReadOnly Property PrintPart As Print3dPartVM
       Get
-         Return m_nId
+         Return m_PrintPart
       End Get
    End Property
 
@@ -110,7 +134,7 @@ Public Class ModifyPart
 
    Public ReadOnly Property ghName As String
       Get
-         Return If(Not String.IsNullOrWhiteSpace(m_sName), m_nId & " - " & m_sName, "Part" & m_nId)
+         Return m_PrintPart.sImportedFileName
       End Get
    End Property
 
@@ -122,13 +146,13 @@ Public Class ModifyPart
    End Property
 
    Sub New(PrintPart As Print3dPartVM)
-      'm_nId = If(Map.refImportPanelVM.ImportPartList.Count = 0, 1, Map.refImportPanelVM.ImportPartList.Max(Function(x) x.m_nId) + 1)
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.PRINT_SOLID, "Print", PrintPart))
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.MACH_START, "Layer Start", PrintPart))
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.RIBS, "Ribs", PrintPart))
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.SHELL_NUMBER, "Reduce Shell Number", PrintPart))
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.AUX_SOLIDS, "Filled Solids", PrintPart))
-      m_LayerList.Add(New ModifyLayer(ImportLayer.LayerType.OTHERS, "Others", PrintPart))
+      m_PrintPart = PrintPart
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.PRINT_SOLID, "Print", PrintPart))
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.MACH_START, "Layer Start", PrintPart))
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.RIBS, "Ribs", PrintPart))
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.SHELL_NUMBER, "Reduce Shell Number", PrintPart))
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.AUX_SOLIDS, "Filled Solids", PrintPart))
+      m_LayerList.Add(New ModifyLayer(ModifyLayer.LayerType.OTHERS, "Others", PrintPart))
    End Sub
 
 End Class
@@ -142,7 +166,7 @@ Public Class ModifyLayer
       RIBS = 3
       SHELL_NUMBER = 4
       AUX_SOLIDS = 5
-      OTHERS = 7
+      OTHERS = 6
    End Enum
 
    Private m_nLayerId As Integer
@@ -200,32 +224,212 @@ Public Class ModifyLayer
          Case LayerType.PRINT_SOLID
             m_nLayerId = PrintPart.nPrintSolidLayerId
             Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
-            Dim sEnitytName As String = ""
-            EgtGetName(nEntityId, sEnitytName)
-            m_EntityList.Add(New ModifyEntity(nEntityId, sEnitytName))
+            Dim sEntitytName As String = ""
+            EgtGetName(nEntityId, sEntitytName)
+            m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
          Case LayerType.MACH_START
             m_nLayerId = PrintPart.nMachStartLayerId
             Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
             Dim sEntitytName As String = ""
             EgtGetName(nEntityId, sEntitytName)
             While nEntityId <> GDB_ID.NULL
-               m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName))
+               m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
                nEntityId = EgtGetNext(nEntityId)
                EgtGetName(nEntityId, sEntitytName)
             End While
          Case LayerType.RIBS
             m_nLayerId = PrintPart.nRibsLayerId
             Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
-            Dim sEnitytName As String = ""
-            EgtGetName(nEntityId, sEnitytName)
-            m_EntityList.Add(New ModifyEntity(nEntityId, sEnitytName))
+            Dim sEntitytName As String = ""
+            EgtGetName(nEntityId, sEntitytName)
+            While nEntityId <> GDB_ID.NULL
+               Dim RibType As Integer = RibEntity.RibTypes.FROMDRAW
+               EgtGetInfo(nEntityId, KEY_RIB_TYPE, RibType)
+               If RibType = RibEntity.RibTypes.FROMIMPORT Then
+                  m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
+               End If
+               nEntityId = EgtGetNext(nEntityId)
+               EgtGetName(nEntityId, sEntitytName)
+            End While
          Case LayerType.SHELL_NUMBER
             m_nLayerId = PrintPart.nShellNumberLayerId
+            Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
+            Dim sEntitytName As String = ""
+            EgtGetName(nEntityId, sEntitytName)
+            While nEntityId <> GDB_ID.NULL
+               Dim ShellType As Integer = ShellNumberEntity.ShellNumberTypes.FROMDRAW
+               EgtGetInfo(nEntityId, KEY_SHELLNBR_TYPE, ShellType)
+               If ShellType = ShellNumberEntity.ShellNumberTypes.FROMIMPORT Then
+                  m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
+               End If
+               nEntityId = EgtGetNext(nEntityId)
+               EgtGetName(nEntityId, sEntitytName)
+            End While
          Case LayerType.AUX_SOLIDS
             m_nLayerId = PrintPart.nAuxSolidsLayerId
+            Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
+            Dim sEntitytName As String = ""
+            EgtGetName(nEntityId, sEntitytName)
+            While nEntityId <> GDB_ID.NULL
+               'Dim ShellType As Integer = ShellNumberEntity.ShellNumberTypes.FROMDRAW
+               'EgtGetInfo(nEntityId, KEY_SHELLNBR_TYPE, ShellType)
+               'If ShellType = ShellNumberEntity.ShellNumberTypes.FROMIMPORT Then
+               m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
+               'End If
+               nEntityId = EgtGetNext(nEntityId)
+               EgtGetName(nEntityId, sEntitytName)
+            End While
          Case LayerType.OTHERS
             m_nLayerId = PrintPart.nOthersLayerId
+            Dim nEntityId As Integer = EgtGetFirstInGroup(m_nLayerId)
+            Dim sEntitytName As String = ""
+            EgtGetName(nEntityId, sEntitytName)
+            While nEntityId <> GDB_ID.NULL
+               m_EntityList.Add(New ModifyEntity(nEntityId, sEntitytName, Me))
+               nEntityId = EgtGetNext(nEntityId)
+               EgtGetName(nEntityId, sEntitytName)
+            End While
       End Select
    End Sub
 
 End Class
+
+Public Class MenuItemVm
+   Inherits VMBase
+
+   ' enita' di origine
+   Private m_OrigEntity As ModifyEntity
+   Private m_OrigLayer As ModifyLayer
+
+   ' pezzo in cui spostare
+   Private m_Part As Print3dPartVM
+
+   ' tipo del layer indicato
+   Private m_Type As ModifyLayer.LayerType
+   Public Property Type As ModifyLayer.LayerType
+      Get
+         Return m_Type
+      End Get
+      Set(value As ModifyLayer.LayerType)
+         m_Type = value
+      End Set
+   End Property
+
+   Public ReadOnly Property sMsg As String
+      Get
+         Dim sType As String = ""
+         Select Case m_Type
+            Case ModifyLayer.LayerType.PRINT_SOLID
+               sType = "Print"
+            Case ModifyLayer.LayerType.MACH_START
+               sType = "Layer Start"
+            Case ModifyLayer.LayerType.RIBS
+               sType = "Ribs"
+            Case ModifyLayer.LayerType.SHELL_NUMBER
+               sType = "Reduce shell number"
+            Case ModifyLayer.LayerType.AUX_SOLIDS
+               sType = "Filled Solids"
+            Case ModifyLayer.LayerType.OTHERS
+               sType = "Others"
+         End Select
+         Return "Move to " & sType
+      End Get
+   End Property
+
+   ' Definizione comando
+   Private m_cmdCommand As ICommand
+
+   Sub New(OrigEntity As ModifyEntity, OrigLayer As ModifyLayer, Type As ModifyLayer.LayerType, Part As Print3dPartVM)
+      m_OrigEntity = OrigEntity
+      m_OrigLayer = OrigLayer
+      m_Type = Type
+      m_Part = Part
+   End Sub
+
+#Region "Cancel"
+
+   Public ReadOnly Property MenuItem_Command As ICommand
+      Get
+         If m_cmdCommand Is Nothing Then
+            m_cmdCommand = New Command(AddressOf Command)
+         End If
+         Return m_cmdCommand
+      End Get
+   End Property
+
+   Public Sub Command()
+      ' recupero layer da pezzo
+      Dim nLayerId As Integer = GDB_ID.NULL
+      Select Case m_Type
+         Case ModifyLayer.LayerType.PRINT_SOLID
+            nLayerId = m_Part.nPrintSolidLayerId
+         Case ModifyLayer.LayerType.MACH_START
+            nLayerId = m_Part.nMachStartLayerId
+         Case ModifyLayer.LayerType.RIBS
+            nLayerId = m_Part.nRibsLayerId
+         Case ModifyLayer.LayerType.SHELL_NUMBER
+            nLayerId = m_Part.nShellNumberLayerId
+         Case ModifyLayer.LayerType.AUX_SOLIDS
+            nLayerId = m_Part.nAuxSolidsLayerId
+         Case ModifyLayer.LayerType.OTHERS
+            nLayerId = m_Part.nOthersLayerId
+      End Select
+      ' sposto entita'
+      If EgtRelocateGlob(m_OrigEntity.nId, nLayerId) Then
+         ' elimino info vecchio layer
+         Select Case m_OrigLayer.Type
+            Case ModifyLayer.LayerType.PRINT_SOLID
+               EgtResetMark(m_OrigEntity.nId)
+            Case ModifyLayer.LayerType.MACH_START
+            Case ModifyLayer.LayerType.RIBS
+               EgtRemoveInfo(m_OrigEntity.nId, KEY_RIB_TYPE)
+            Case ModifyLayer.LayerType.SHELL_NUMBER
+               EgtRemoveInfo(m_OrigEntity.nId, KEY_SHELLNBR_TYPE)
+            Case ModifyLayer.LayerType.AUX_SOLIDS
+               EgtRemoveInfo(m_OrigEntity.nId, KEY_AUXSOLID_TYPE)
+            Case ModifyLayer.LayerType.OTHERS
+         End Select
+         ' sposto in lista
+         m_OrigLayer.EntityList.Remove(m_OrigEntity)
+         Dim NewPart As ModifyPart = Map.refModifyPartPanelVM.ModifyPartList.FirstOrDefault(Function(x) x.PrintPart.nPartId = m_Part.nPartId)
+         If Not IsNothing(NewPart) Then
+            Dim NewLayer As ModifyLayer = NewPart.LayerList.FirstOrDefault(Function(x) x.Type = m_Type)
+            If Not IsNothing(NewLayer) Then
+               NewLayer.EntityList.Add(m_OrigEntity)
+               ' aggiorno riferimenti nell'entita'
+               m_OrigEntity.UpdateOrigLayer(NewLayer)
+            End If
+         End If
+         ' aggiungo info nuovo layer
+         Select Case m_Type
+            Case ModifyLayer.LayerType.PRINT_SOLID
+               EgtSetName(m_OrigEntity.nId, PRINT_SOLID)
+               EgtSetColor(m_OrigEntity.nId, c3Print)
+            Case ModifyLayer.LayerType.MACH_START
+               EgtSetName(m_OrigEntity.nId, LAY_MACH_START)
+               EgtSetColor(m_OrigEntity.nId, c3MachStart)
+            Case ModifyLayer.LayerType.RIBS
+               EgtSetName(m_OrigEntity.nId, LAY_RIBS)
+               EgtSetInfo(m_OrigEntity.nId, KEY_RIB_TYPE, RibEntity.RibTypes.FROMIMPORT)
+               EgtSetColor(m_OrigEntity.nId, c3Rib)
+            Case ModifyLayer.LayerType.SHELL_NUMBER
+               EgtSetName(m_OrigEntity.nId, LAY_SHELL_NBR)
+               EgtSetInfo(m_OrigEntity.nId, KEY_SHELLNBR_TYPE, ShellNumberEntity.ShellNumberTypes.FROMIMPORT)
+               EgtSetColor(m_OrigEntity.nId, c3ShellNumber)
+            Case ModifyLayer.LayerType.AUX_SOLIDS
+               EgtSetName(m_OrigEntity.nId, LAY_AUX_SOLIDS)
+               EgtSetInfo(m_OrigEntity.nId, KEY_AUXSOLID_TYPE, RibEntity.RibTypes.FROMIMPORT)
+               EgtSetColor(m_OrigEntity.nId, c3AuxSolids)
+            Case ModifyLayer.LayerType.OTHERS
+               EgtSetName(m_OrigEntity.nId, LAY_OTHERS)
+               EgtSetColor(m_OrigEntity.nId, c3Others)
+         End Select
+         EgtDraw()
+         ' aggiorno riferimenti nel context menu item
+         m_OrigEntity.UpdateContextMenu(m_OrigEntity.OrigLayer)
+      End If
+   End Sub
+
+#End Region ' Cancel
+
+End Class
\ No newline at end of file
diff --git a/Icarus/SliceManager/SliceManagerVM.vb b/Icarus/SliceManager/SliceManagerVM.vb
index d414ca5..2bfdc93 100644
--- a/Icarus/SliceManager/SliceManagerVM.vb
+++ b/Icarus/SliceManager/SliceManagerVM.vb
@@ -496,7 +496,7 @@ Public Class SliceManagerVM
          m_bCalculating = False
          Return
       End If
-      If IsNothing(Map.refTopPanelVM.SelMachining) Then
+      If IsNothing(Map.refTopPanelVM.SelMachining) OrElse IsNothing(Map.refTopPanelVM.CurrMachining) OrElse Map.refTopPanelVM.CurrMachining.dCurrStrandH <= 0 Then
          MessageBox.Show("No print parameters set!", "Error", MessageBoxButton.OK, MessageBoxImage.Error)
          m_bCalculating = False
          Return
diff --git a/Icarus/TopPanel/TopPanelVM.vb b/Icarus/TopPanel/TopPanelVM.vb
index d2c0f26..4e6c414 100644
--- a/Icarus/TopPanel/TopPanelVM.vb
+++ b/Icarus/TopPanel/TopPanelVM.vb
@@ -267,7 +267,7 @@ Public Class TopPanelVM
          m_MachiningList.Remove(MachiningIndex.Empty())
       End If
       ' se nuova lavorazione e' none
-      If SelMachining.sGUID = Guid.Empty Then
+      If SelMachining.sGUID = Guid.Empty AndAlso Not MachiningList.Any(Function(x) x.sGUID = MachiningIndex.Empty.sGUID) Then
          ' aggiungo lavorazione vuota
          MachiningList.Insert(0, MachiningIndex.Empty())
       End If
diff --git a/Icarus/Utility/GeomEntityColors.vb b/Icarus/Utility/GeomEntityColors.vb
new file mode 100644
index 0000000..2f007f6
--- /dev/null
+++ b/Icarus/Utility/GeomEntityColors.vb
@@ -0,0 +1,57 @@
+Imports EgtUILib
+
+Module GeomEntityColors
+
+   Private m_c3Print As Color3d
+   Public ReadOnly Property c3Print As Color3d
+      Get
+         Return m_c3Print
+      End Get
+   End Property
+
+   Private m_c3MachStart As Color3d
+   Public ReadOnly Property c3MachStart As Color3d
+      Get
+         Return m_c3MachStart
+      End Get
+   End Property
+
+   Private m_c3Rib As Color3d
+   Public ReadOnly Property c3Rib As Color3d
+      Get
+         Return m_c3Rib
+      End Get
+   End Property
+
+   Private m_c3ShellNumber As Color3d
+   Public ReadOnly Property c3ShellNumber As Color3d
+      Get
+         Return m_c3ShellNumber
+      End Get
+   End Property
+
+   Private m_c3AuxSolids As Color3d
+   Public ReadOnly Property c3AuxSolids As Color3d
+      Get
+         Return m_c3AuxSolids
+      End Get
+   End Property
+
+   Private m_c3Others As Color3d
+   Public ReadOnly Property c3Others As Color3d
+      Get
+         Return m_c3Others
+      End Get
+   End Property
+
+   Sub New()
+      ' imposto colori superfici
+      m_c3Print.FromColor(System.Drawing.Color.Yellow)
+      m_c3MachStart.FromColor(System.Drawing.Color.Red)
+      m_c3Rib.FromColor(System.Drawing.Color.MediumOrchid)
+      m_c3ShellNumber.FromColor(System.Drawing.Color.Lime)
+      m_c3AuxSolids.FromColor(System.Drawing.Color.DarkGoldenrod)
+      m_c3Others.FromColor(System.Drawing.Color.LightGray)
+   End Sub
+
+End Module