diff --git a/EgtMachKernel.rc b/EgtMachKernel.rc
index d31586c..22f3368 100644
Binary files a/EgtMachKernel.rc and b/EgtMachKernel.rc differ
diff --git a/Operation.cpp b/Operation.cpp
index 78af160..64e6220 100644
--- a/Operation.cpp
+++ b/Operation.cpp
@@ -1144,10 +1144,16 @@ Operation::AdjustStartEndMovements( void)
      // imposto l'utensile precedente per i calcoli macchina
       if ( ! m_pMchMgr->SetCalcTool( pPrevOp->GetToolName(), pPrevOp->GetHeadName(), pPrevOp->GetExitNbr()))
          return false ;
-     // ricalcolo risalita di lavorazione precedente
-      pPrevOp->RemoveRise() ;
-      if ( ! pPrevOp->AddRise( vAxVal))
-         return false ;
+     // ricalcolo risalita di lavorazione precedente (se già calcolata)
+      if ( pPrevOp->RemoveRise()) {
+         if ( ! pPrevOp->AddRise( vAxVal))
+            return false ;
+      }
+      else {
+        // recupero posizione home
+         if ( ! m_pMchMgr->GetAllCalcAxesHomePos( vAxVal))
+            return false ;
+      }
      // imposto l'utensile per i calcoli macchina
       if ( ! m_pMchMgr->SetCalcTool( GetToolName(), GetHeadName(), GetExitNbr()))
          return false ;
@@ -1653,7 +1659,7 @@ Operation::TestCollisionAvoid( const DBLVECTOR& vAxStart, const DBLVECTOR& vAxEn
       }
      // Eseguo controllo
       BBox3d b3Head ;
-      m_pGeomDB->GetGlobalBBox( pMch->GetCurrHead(), b3Head) ;
+      m_pGeomDB->GetGlobalBBox( pMch->GetCurrHead(), b3Head, BBF_ONLY_VISIBLE) ;
       for ( const auto nRawId : vRawId) {
          BBox3d b3Raw ;
          int nRawSolidId = m_pGeomDB->GetFirstNameInGroup( nRawId, MACH_RAW_SOLID) ;