diff --git a/PartPreviewWindow/ViewControls3D.cs b/PartPreviewWindow/ViewControls3D.cs
index 614207b38..906864629 100644
--- a/PartPreviewWindow/ViewControls3D.cs
+++ b/PartPreviewWindow/ViewControls3D.cs
@@ -285,21 +285,22 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 				SiblingRadioButtonList = buttonGroupB,
 				Name = "Model View Button",
 				Checked = printer?.ViewState.ViewMode == PartViewMode.Model || printer == null,
-				ToolTipText = "Model".Localize(),
+				ToolTipText = "Model View".Localize(),
 				Margin = commonMargin
 			};
 			modelViewButton.Click += SwitchModes_Click;
 			buttonGroupB.Add(modelViewButton);
 			AddChild(modelViewButton);
 
-			iconPath = Path.Combine("ViewTransformControls", "3d.png");
+			iconPath = Path.Combine("ViewTransformControls", "gcode_3d.png");
 			layers3DButton = new RadioIconButton(AggContext.StaticData.LoadIcon(iconPath, IconColor.Theme), theme)
 			{
 				SiblingRadioButtonList = buttonGroupB,
 				Name = "Layers3D Button",
 				Checked = printer?.ViewState.ViewMode == PartViewMode.Layers3D,
-				ToolTipText = "3D Layers".Localize(),
-				Margin = commonMargin
+				ToolTipText = "3D Layer View".Localize(),
+				Margin = commonMargin,
+				Enabled = isPrinterType
 			};
 			layers3DButton.Click += SwitchModes_Click;
 			buttonGroupB.Add(layers3DButton);
@@ -309,14 +310,15 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 				this.AddChild(layers3DButton);
 			}
 
-			iconPath = Path.Combine("ViewTransformControls", "2d.png");
+			iconPath = Path.Combine("ViewTransformControls", "gcode_2d.png");
 			layers2DButton = new RadioIconButton(AggContext.StaticData.LoadIcon(iconPath, IconColor.Theme), theme)
 			{
 				SiblingRadioButtonList = buttonGroupB,
 				Name = "Layers2D Button",
 				Checked = printer?.ViewState.ViewMode == PartViewMode.Layers2D,
-				ToolTipText = "2D Layers".Localize(),
-				Margin = commonMargin
+				ToolTipText = "2D Layer View".Localize(),
+				Margin = commonMargin,
+				Enabled = isPrinterType
 			};
 			layers2DButton.Click += SwitchModes_Click;
 			buttonGroupB.Add(layers2DButton);
@@ -434,7 +436,6 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 				BackgroundColor = theme.MinimalShade,
 				GradientDistance = -1,
 				DrawArrow = true,
-				AlignToRightEdge = true,
 				Margin = theme.ButtonSpacing,
 			};
 
@@ -443,6 +444,11 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 
 		private void SwitchModes_Click(object sender, MouseEventArgs e)
 		{
+			if (!IsPrinterMode)
+			{
+				return;
+			}
+
 			if (sender is GuiWidget widget)
 			{
 				if (widget.Name == "Layers2D Button")
diff --git a/SlicerConfiguration/SliceSettingsWidget.cs b/SlicerConfiguration/SliceSettingsWidget.cs
index 92cc2e237..9560791c7 100644
--- a/SlicerConfiguration/SliceSettingsWidget.cs
+++ b/SlicerConfiguration/SliceSettingsWidget.cs
@@ -469,7 +469,16 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 				switch (settingData.DataEditType)
 				{
 					case SliceSettingData.DataEditTypes.INT:
-						uiField = new IntField();
+
+						var intField = new IntField();
+						uiField = intField;
+
+						if (settingData.SlicerConfigName == "extruder_count")
+						{
+							intField.MaxValue = 4;
+							intField.MinValue = 0;
+						}
+
 						break;
 
 					case SliceSettingData.DataEditTypes.DOUBLE:
diff --git a/SlicerConfiguration/UIFields/IntField.cs b/SlicerConfiguration/UIFields/IntField.cs
index d258b71ca..c5ade67d5 100644
--- a/SlicerConfiguration/UIFields/IntField.cs
+++ b/SlicerConfiguration/UIFields/IntField.cs
@@ -1,5 +1,5 @@
 /*
-Copyright (c) 2017, Lars Brubaker, John Lewin
+Copyright (c) 2018, Lars Brubaker, John Lewin
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
@@ -27,6 +27,7 @@ of the authors and should not be interpreted as representing official policies,
 either expressed or implied, of the FreeBSD Project.
 */
 
+using System;
 
 namespace MatterHackers.MatterControl.SlicerConfiguration
 {
@@ -34,10 +35,17 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 	{
 		private int intValue;
 
+		public int MinValue { get; set; } = int.MinValue;
+
+		public int MaxValue { get; set; } = int.MaxValue;
+
 		protected override string ConvertValue(string newValue)
 		{
 			decimal.TryParse(newValue, out decimal currentValue);
-			intValue = (int)currentValue;
+
+			// Clamp to range
+			intValue = Math.Min((int)currentValue, this.MaxValue);
+			intValue = Math.Max(intValue, this.MinValue);
 
 			return intValue.ToString();
 		}
diff --git a/StaticData/Icons/ViewTransformControls/2d.png b/StaticData/Icons/ViewTransformControls/gcode_2d.png
similarity index 100%
rename from StaticData/Icons/ViewTransformControls/2d.png
rename to StaticData/Icons/ViewTransformControls/gcode_2d.png
diff --git a/StaticData/Icons/ViewTransformControls/3d.png b/StaticData/Icons/ViewTransformControls/gcode_3d.png
similarity index 100%
rename from StaticData/Icons/ViewTransformControls/3d.png
rename to StaticData/Icons/ViewTransformControls/gcode_3d.png
diff --git a/Submodules/agg-sharp b/Submodules/agg-sharp
index 62ffc915f..e28826c49 160000
--- a/Submodules/agg-sharp
+++ b/Submodules/agg-sharp
@@ -1 +1 @@
-Subproject commit 62ffc915f217c8a2232810fb4f567f9b4b1009f3
+Subproject commit e28826c49a73ed885dd459b4631f021d6d26406c