Index: sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml
===================================================================
diff -u -r07121b02499a4c929c5b5e8bd804a67539574c1b -rc70815ad2b3beadf61832f2e4d12eb90d476e020
--- sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml	(.../PreTreatmentStack.qml)	(revision 07121b02499a4c929c5b5e8bd804a67539574c1b)
+++ sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml	(.../PreTreatmentStack.qml)	(revision c70815ad2b3beadf61832f2e4d12eb90d476e020)
@@ -62,6 +62,11 @@
 
     stackView.onCurrentItemChanged: if ( stackView.currentItem != _pretreatmentInstallation ) { _headerBar.activeStack = stackView }
 
+    function setPage(vPage, vCondition) {
+        _root.stackStepIndex = _root.stepKeys.indexOf(vPage.stepIndex)
+        page( vPage , vCondition)
+    }
+
     // dynamically rebuild map 🗺️ when entering pretreatment.
     // { step key (enum) : step name (string) } -- decided to use 2 parallel list for better indexing
     function rebuildMap() {
@@ -100,22 +105,22 @@
     function confirmClicked() {
         switch ( stepKeys[_root.stackStepIndex] ) {
         case PreTreatmentStack.Step.Concentrates:
-            page ( _pretreatmentInstallation )
+            setPage ( _pretreatmentInstallation )
             break
         case PreTreatmentStack.Step.Installation:
             if ( vSettings.advancedMode )   { vPreTreatmentAdjustmentDisposablesConfirm.doConfirm() }
             else                            { _pretreatmentInstallation.continueClicked()           }
             break
         case PreTreatmentStack.Step.SelfTests:
-            page ( _pretreatmentPrime )
+            setPage ( _pretreatmentPrime )
             break
         case PreTreatmentStack.Step.Prime:
             if ( _pretreatmentPrime.timeCircleProgressValue === 0 ) { vPreTreatmentAdjustmentDisposablesPrime.doPrime();        }
-            page ( _pretreatmentCreate )
+            setPage ( _pretreatmentCreate )
             break
         case PreTreatmentStack.Step.CreateRx:
             _pretreatmentCreate.confirmButtonClicked()
-            if ( vTreatmentCreate.parametersValidated ) { page ( _pretreatmentConnect ) }
+            if ( vTreatmentCreate.parametersValidated ) { setPage ( _pretreatmentConnect ) }
             break
         case PreTreatmentStack.Step.Connect:
             vPreTreatmentAdjustmentStartTreatment.doStart()
@@ -222,46 +227,25 @@
     }
 
     // Pages
-    PreTreatmentBase    { id:   _pretreatmentConcentrates
-        instructionBased    : true
-        onVisibleChanged    : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.Concentrates); updateModel()    }
-    }
+    PreTreatmentBase            { id:   _pretreatmentConcentrates;  stepIndex:  PreTreatmentStack.Step.Concentrates;    instructionBased: true  }
+    PreTreatmentInstallStack    { id:   _pretreatmentInstallation;  stepIndex:  PreTreatmentStack.Step.Installation                             }
+    PreTreatmentSelfTests       { id:   _pretreatmentSelfTests;     stepIndex:  PreTreatmentStack.Step.SelfTests                                }
+    PreTreatmentPrime           { id:   _pretreatmentPrime;         stepIndex:  PreTreatmentStack.Step.Prime                                    }
+    PreTreatmentCreate          { id:   _pretreatmentCreate;        stepIndex:  PreTreatmentStack.Step.CreateRx                                 }
+    PreTreatmentBase            { id:   _pretreatmentConnect;       stepIndex:  PreTreatmentStack.Step.Connect;         instructionBased: true  }
 
-    PreTreatmentInstallStack { id: _pretreatmentInstallation
-        onVisibleChanged    : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.Installation);  initStack()     }
-    }
-
-    PreTreatmentSelfTests{ id:   _pretreatmentSelfTests
-        onVisibleChanged    : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.SelfTests);                     }
-    }
-
-    PreTreatmentPrime    { id:   _pretreatmentPrime
-        onVisibleChanged    : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.Prime);                         }
-    }
-
-    PreTreatmentCreate  { id:   _pretreatmentCreate
-        onVisibleChanged        : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.CreateRx)                   }
-        showCreateRxHeaderButton: false
-    }
-
-    PreTreatmentBase    { id:   _pretreatmentConnect
-        instructionBased        : true
-        onVisibleChanged        : if (visible) { _root.stackStepIndex = stepKeys.indexOf(PreTreatmentStack.Step.Connect);   updateModel()   }
-        showCreateRxHeaderButton: false
-    }
-
     // Slots
     Connections { target: vTDOpMode
-        function onPreTreatmentChanged( vValue ) {  if ( ! vTreatmentCreate.txCode )    { vTreatmentCreate.generateTxCode()                  }
-                                                    if ( vSettings.advancedMode )       { page ( _pretreatmentInstallation      , vValue    )}
-                                                    else                                { page ( _pretreatmentConcentrates      , vValue    )}
+        function onPreTreatmentChanged( vValue ) {  if ( ! vTreatmentCreate.txCode )    { vTreatmentCreate.generateTxCode()                     }
+                                                    if ( vSettings.advancedMode )       { setPage ( _pretreatmentInstallation      , vValue    )}
+                                                    else                                { setPage ( _pretreatmentConcentrates      , vValue    )}
         }
     }
 
     // Installation
     Connections { target: _pretreatmentInstallation
-        function onGoToNextStep ()      { page ( _pretreatmentSelfTests     )}
-        function onGoToPreviousStep ()  { page ( _pretreatmentConcentrates  )}
+        function onGoToNextStep ()      { setPage ( _pretreatmentSelfTests     )}
+        function onGoToPreviousStep ()  { setPage ( _pretreatmentConcentrates  )}
     }
 
     // priming
@@ -278,7 +262,7 @@
     // creat rx
     Connections{ target: vTreatmentCreate
         function onDidValidationPass            ( ) {
-            if ( _pretreatmentCreate.visible) { page ( _pretreatmentConnect ) }
+            if ( _pretreatmentCreate.visible) { setPage ( _pretreatmentConnect ) }
         }
     }