diff --git a/ComTester.py b/ComTester.py
index 15dd96ea5..e8a75417b 100644
--- a/ComTester.py
+++ b/ComTester.py
@@ -27,6 +27,7 @@
 
 # This is to test connection and printing. We use it with com0com 
 # to validate MatterControl under various situations.
+from time import sleep
 import sys
 import argparse
 import serial
@@ -65,6 +66,7 @@ def main(argv):
 		if len(line) > 0:
 			print(line)
 			response = getCorrectResponse(line)
+			sleep(0.02)
 			print response
 			ser.write(response)
 	ser.close()
diff --git a/PartPreviewWindow/ViewGcodeBasic.cs b/PartPreviewWindow/ViewGcodeBasic.cs
index 78c6ca8bd..c934d98cb 100644
--- a/PartPreviewWindow/ViewGcodeBasic.cs
+++ b/PartPreviewWindow/ViewGcodeBasic.cs
@@ -334,7 +334,13 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
         private void SetAnimationPosition()
         {
             int currentLayer = PrinterConnectionAndCommunication.Instance.CurrentlyPrintingLayer;
-            if (currentLayer >= 0)
+            if (currentLayer <= 0)
+            {
+                selectLayerSlider.Value = 0;
+                layerRenderRatioSlider.SecondValue = 0;
+                layerRenderRatioSlider.FirstValue = 0;
+            }
+            else
             {
                 selectLayerSlider.Value = currentLayer-1;
                 layerRenderRatioSlider.SecondValue = PrinterConnectionAndCommunication.Instance.RatioIntoCurrentLayer;
diff --git a/PrinterCommunication/PrinterConnectionAndCommunication.cs b/PrinterCommunication/PrinterConnectionAndCommunication.cs
index 939d72701..ec965a3c9 100644
--- a/PrinterCommunication/PrinterConnectionAndCommunication.cs
+++ b/PrinterCommunication/PrinterConnectionAndCommunication.cs
@@ -684,7 +684,7 @@ namespace MatterHackers.MatterControl.PrinterCommunication
                     {
                         if (currentIndex < loadedGCode.IndexOfChangeInZ[zIndex])
                         {
-                            return zIndex-1;
+                            return zIndex;
                         }
                     }
 
@@ -720,11 +720,15 @@ namespace MatterHackers.MatterControl.PrinterCommunication
                     && currentIndex < loadedGCode.Count)
                 {
                     int currentLayer = CurrentlyPrintingLayer;
-                    int startIndex = loadedGCode.IndexOfChangeInZ[currentLayer];
-                    int endIndex = loadedGCode.Count - 1;
-                    if (currentLayer < loadedGCode.NumChangesInZ - 2)
+                    int startIndex = 0;
+                    if (currentLayer > 0)
                     {
-                        endIndex = loadedGCode.IndexOfChangeInZ[currentLayer + 1] - 1;
+                        startIndex = loadedGCode.IndexOfChangeInZ[currentLayer-1];
+                    }
+                    int endIndex = loadedGCode.Count - 1;
+                    if (currentLayer < loadedGCode.NumChangesInZ - 1)
+                    {
+                        endIndex = loadedGCode.IndexOfChangeInZ[currentLayer];
                     }
 
                     int deltaFromStart = Math.Max(0, currentIndex - startIndex);
diff --git a/StaticData/Translations/Master.txt b/StaticData/Translations/Master.txt
index 8a01f7d08..602e980e4 100644
--- a/StaticData/Translations/Master.txt
+++ b/StaticData/Translations/Master.txt
@@ -3029,3 +3029,9 @@ Translated:Location: 'Advanced Controls' -> 'Slice Settings' -> 'Filament' -> 'F
 English:Save Slice Configuration
 Translated:Save Slice Configuration
 
+English:Printing: {0}
+Translated:Printing: {0}
+
+English:Finished Print: {0}
+Translated:Finished Print: {0}
+