diff --git a/.gitignore b/.gitignore
index bdc3535..50cb4ca 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
+# Wix installer generated files
+*.wixobj
+*.wixpdb
+
 # Build Folders (you can keep bin if you'd like, to store dlls and pdbs)
 [Bb]in/
 [Oo]bj/
diff --git a/GUI/GUI.csproj b/GUI/GUI.csproj
index cd34636..4dcf873 100644
--- a/GUI/GUI.csproj
+++ b/GUI/GUI.csproj
@@ -8,7 +8,7 @@
     <OutputType>WinExe</OutputType>
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>GUI</RootNamespace>
-    <AssemblyName>GUI</AssemblyName>
+    <AssemblyName>PathCAM</AssemblyName>
     <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <PublishUrl>publish\</PublishUrl>
@@ -48,6 +48,9 @@
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
+  <PropertyGroup>
+    <ApplicationIcon>icon.ico</ApplicationIcon>
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="OpenTK, Version=1.1.0.0, Culture=neutral, PublicKeyToken=bad199fe84eb3df4, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
@@ -176,6 +179,9 @@
       <Install>false</Install>
     </BootstrapperPackage>
   </ItemGroup>
+  <ItemGroup>
+    <Content Include="icon.ico" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$(SolutionDir)\.nuget\NuGet.targets" Condition="Exists('$(SolutionDir)\.nuget\NuGet.targets')" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/GUI/TriangleMeshGUI.cs b/GUI/TriangleMeshGUI.cs
index 29ac332..2f29195 100644
--- a/GUI/TriangleMeshGUI.cs
+++ b/GUI/TriangleMeshGUI.cs
@@ -123,8 +123,8 @@ public void Draw()
             
             // Draw the slice at the mouse point
             //GL.Disable(EnableCap.Lighting);
-            //GL.Color3(Color.White);
-            //Slice s = new Slice(this, new Plane(Vector3.UnitZ, mousePoint));
+            //GL.Color3(Color.Black);
+            //Slice s = new Slice(this, new Plane(Vector3.UnitZ, mouseHoverPoint));
             //foreach (var line in s.GetLines(Slice.LineType.All))
             //{
             //    GL.Begin(PrimitiveType.LineLoop);
@@ -134,6 +134,18 @@ public void Draw()
             //    }
             //    GL.End();
             //}
+            //GL.Translate(0, 0, .25f);
+            //GL.Color3(Color.DarkBlue);
+            //GL.Begin(PrimitiveType.Triangles);
+            //foreach (var tri in s.Triangles())
+            //{
+            //    foreach (var point in tri.Vertices)
+            //    {
+            //        GL.Vertex3(point);
+            //    }
+            //}
+            //GL.End();
+            //GL.Translate(0, 0, -.25f);
             //GL.Enable(EnableCap.Lighting);
 
             // Draw the triangles & edges
@@ -148,16 +160,16 @@ public void Draw()
                 }
                 lastNumTriangles = TriangleCount;
             }
-
+            
             if (triangleDisplayList >= 0)
             {
                 GL.Color3(triangleColor);
                 GL.CallList(triangleDisplayList);
-
+            
                 GL.Disable(EnableCap.Lighting);
                 GL.Color3(lineColor);
                 GL.CallList(lineDisplayList);
-
+            
                 GL.Color3(badLineColor);
                 GL.CallList(badLineDisplayList);
                 GL.Enable(EnableCap.Lighting);
@@ -170,7 +182,7 @@ public void Draw()
                     lineDisplayList = GL.GenLists(1);
                     badLineDisplayList = GL.GenLists(1);
                 }
-
+            
                 // Triangles
                 GL.Color3(triangleColor);
                 if (useDisplayLists)
@@ -191,7 +203,7 @@ public void Draw()
                 {
                     GL.EndList();
                 }
-
+            
                 // Outside Edges
                 List<LineSegment> edges = new List<LineSegment>();
                 List<LineSegment> badEdges = new List<LineSegment>();
@@ -211,7 +223,7 @@ public void Draw()
                         badEdges.Add(edge.LineSegment);
                     }
                 }
-
+            
                 GL.Disable(EnableCap.Lighting);
                 GL.Color3(lineColor);
                 if (useDisplayLists)
@@ -229,7 +241,7 @@ public void Draw()
                 {
                     GL.EndList();
                 }
-
+            
                 GL.Color3(badLineColor);
                 if (useDisplayLists)
                 {
diff --git a/Geometry/Intersect.cs b/Geometry/Intersect.cs
index 5c4cfc4..df7ad1c 100644
--- a/Geometry/Intersect.cs
+++ b/Geometry/Intersect.cs
@@ -112,6 +112,7 @@ public class TrianglePlaneIntersect
         private Vector3 pointA;
         private Vector3 pointB;
         private bool intersects = false;
+        public bool all_intersect = false;
         public TrianglePlaneIntersect(Triangle triangle, Plane plane)
         {
             // Find the intersections between edges on the triangle and the plane.
@@ -129,14 +130,64 @@ public TrianglePlaneIntersect(Triangle triangle, Plane plane)
             {
                 float d1 = distances[i];
                 float d2 = distances[(i + 1) % 3];
+                float d3 = distances[(i + 2) % 3];
                 Vector3 v1 = vertices[i];
                 Vector3 v2 = vertices[(i + 1) % 3];
+                Vector3 v3 = vertices[(i + 2) % 3];
+
                 if (d1 * d2 < 0)
                 {
-                    // Edge of the triangle crosses the plane, interpolate to get the intersection point
+                    // One point on the edge from D1 to D2
                     Vector3 intersect = new Vector3(v2 * d1 - v1 * d2) / (d1 - d2);
                     onPlane.Add(intersect);
+                    if (d3 == 0)
+                    {
+                        // Other point is on D3
+                        onPlane.Add(v3);
+                        break;
+                    }
+                    else
+                    {
+                        if (d1 * d3 < 0)
+                        {
+                            // Intersect with v1 to v3
+                            onPlane.Add(new Vector3(v3 * d1 - v1 * d3) / (d1 - d3));
+                            break;
+                        }
+                        else if (d2 * d3 < 0)
+                        {
+                            // Intersect with v2 to v3
+                            onPlane.Add(new Vector3(v3 * d2 - v2 * d3) / (d2 - d3));
+                            break;
+                        }
+                        else
+                        {
+                            // how the heck would we get here?
+                        }
+                    }
+                }
+                if (d1 == 0 && d2 == 0)
+                {
+                    if (d3 == 0)
+                    {
+                        // Triangle intersects perfectly with the plane - need to return all 3 edges here?
+                        all_intersect = true;
+                        break;
+                    }
+                    else
+                    {
+                        onPlane.Add(v1);
+                        onPlane.Add(v2);
+                        break;
+                    }
                 }
+
+                //if (d1 * d2 < 0)
+                //{
+                //    // Edge of the triangle crosses the plane, interpolate to get the intersection point
+                //    Vector3 intersect = new Vector3(v2 * d1 - v1 * d2) / (d1 - d2);
+                //    onPlane.Add(intersect);
+                //}
             }
 
             if (onPlane.Count == 2)
diff --git a/Geometry/Loaders/DAE_Loader.cs b/Geometry/Loaders/DAE_Loader.cs
index 7f6b448..c5209df 100644
--- a/Geometry/Loaders/DAE_Loader.cs
+++ b/Geometry/Loaders/DAE_Loader.cs
@@ -108,6 +108,10 @@ public Source FindSourceById(Source[] sources, string id)
 
         public float[] PositionFloats()
         {
+            if (vertices == null)
+            {
+                return new float[] { };
+            }
             Input i = FindInputBySemantic(vertices.input, "POSITION");
             Source s = FindSourceById(sources, i.source);
             IEnumerable<float> floats = s.float_array.Split(new char[] { ' ' }).Select(float_str => float.Parse(float_str));
diff --git a/Geometry/Slice.cs b/Geometry/Slice.cs
index 9abc2a1..02b4f99 100644
--- a/Geometry/Slice.cs
+++ b/Geometry/Slice.cs
@@ -48,30 +48,50 @@ public Slice(TriangleMesh mesh, Plane plane)
             //GL.LineWidth(2);
             //GL.Begin(PrimitiveType.Lines);
             //float height = 0;
-            LineHandler lineHandler = new LineHandler();
-            
-            // Slice at 3 levels and combine all segments - this obviates floating point comparison handling.
+
+            // Slice at 3 levels and combine all segments - this obviates dealing with triangles that are exactly on the plane.
             for (int i = -1; i <= 1; i++)
             {
                 Vector3 offset = plane.Normal * 0.0001f * (float)i;
+                LineHandler lineHandler = new LineHandler(0.0f);
                 Plane testPlane = new Plane(plane.Normal, plane.Point + offset);
                 foreach (Triangle t in mesh.Triangles)
                 {
                     var intersect = new TrianglePlaneIntersect(t, testPlane);
                     if (intersect.Intersects)
                     {
-                        lineHandler.AddSegment(intersect.PointA - offset, intersect.PointB - offset);
+                        lineHandler.AddSegment(intersect.PointA, intersect.PointB);
                         //GL.Color3(Color.Blue);
                         //GL.Vertex3(intersect.PointA + new Vector3(0, 0, height + .01f));
                         //GL.Color3(Color.Red);
                         //GL.Vertex3(intersect.PointB + new Vector3(0, 0, height + .01f));
                     }
+                    else if (intersect.all_intersect && Vector3.Dot(t.Plane.Normal, testPlane.Normal) > 0.5f)
+                    {
+                        // Entire triangle intersects
+                        // Add all the triangle edges (TODO: clean this up...)
+                        List<Vector3> vertices = new List<Vector3>(t.Vertices);
+                        for (int a = 0; a < 3; a++)
+                        {
+                            Vector3 v1 = vertices[a];
+                            Vector3 v2 = vertices[(a + 1) % 3];
+                            lineHandler.AddSegment(v1, v2);
+                        }
+                    }
+                }
+                if (this.polyTree == null)
+                {
+                    Init(lineHandler.GetOuterLoops(), plane);
+                }
+                else
+                {
+                    Slice s = new Slice(lineHandler.GetOuterLoops(), plane);
+                    this.Add(s);
                 }
             }
             //GL.End();
             //GL.Enable(EnableCap.Lighting);
             //GL.LineWidth(1);
-            Init(lineHandler.GetOuterLoops(), plane);
         }
 
         public Slice(Slice fromSlice)
@@ -541,12 +561,13 @@ public override string ToString()
             // All units are in thousandths of an inch
             // Floats have a precision of about 7 digits.
             // An epsilion value of 0.001f will be valid for about +-100 inches
-            private const float epsilon = 0.01f;
+            private float epsilon = 0.001f;
             private List<VectorWrapper> vectors = new List<VectorWrapper>();
             private List<Segment> segments = new List<Segment>();
 
-            public LineHandler()
+            public LineHandler(float epsilon = 0.01f)
             {
+                this.epsilon = epsilon;
             }
 
             public void AddSegment (Vector3 a, Vector3 b)
@@ -561,7 +582,8 @@ public void AddSegment (Vector3 a, Vector3 b)
 
             private VectorWrapper FindVectorWrapper(Vector3 v)
             {
-                int index = vectors.FindIndex(vectorwrapper => (vectorwrapper.vector - v).Length < epsilon);
+                //int index = vectors.FindIndex(vectorwrapper => (vectorwrapper.vector - v).Length <= epsilon);
+                int index = vectors.FindIndex(vectorwrapper => vectorwrapper.vector == v);
                 if (index < 0)
                 {
                     vectors.Add(new VectorWrapper(v));
diff --git a/Installer/PathCAM.msi b/Installer/PathCAM.msi
new file mode 100644
index 0000000..668593f
Binary files /dev/null and b/Installer/PathCAM.msi differ
diff --git a/Installer/PathCAM.xml b/Installer/PathCAM.xml
new file mode 100644
index 0000000..69d11b8
--- /dev/null
+++ b/Installer/PathCAM.xml
@@ -0,0 +1,94 @@
+<?xml version='1.0' encoding='windows-1252'?>
+<Wix xmlns='http://schemas.microsoft.com/wix/2006/wi'>
+
+  <Product Name='PathCAM' Id='8454EA61-B731-447D-80DF-488DC83D3986' UpgradeCode='1419EB08-9DC9-4986-B9F7-6B66377D4776'
+    Language='1033' Codepage='1252' Version='1.0.0' Manufacturer='Subvertlab'>
+
+    <Package Id='*' Keywords='Installer' Description="PathCAM Installer"
+      Comments='PathCAM - Toolpath generation software for CNC robots' Manufacturer='Subvertlab'
+      InstallerVersion='100' Languages='1033' Compressed='yes' SummaryCodepage='1252' />
+	  
+	  <Media Id='1' Cabinet='PathCAM.cab' EmbedCab='yes' DiskPrompt='CD-ROM #1' />
+	  <Property Id='DiskPrompt' Value="Installation Source[1]" />
+	  
+	  <Directory Id='TARGETDIR' Name='SourceDir'>
+	  
+	  
+	  <Directory Id='ProgramFilesFolder' Name='PFiles'>
+        <!--Directory Id='Subvertlab' Name='Subvertlab'-->
+          <Directory Id='INSTALLDIR' Name='PathCAM'>
+		  
+			<Component Id='MainExecutable' Guid='25FD7BF3-A7E8-4EC1-A8A0-7150B675AE5D'>
+				
+			  <File Id='PathCAMEexe' Name='PathCAM.exe' DiskId='1' Source='..\GUI\bin\Release\PathCAM.exe' KeyPath='yes'>
+				<Shortcut Id="startmenuPathCAM" Directory="ProgramMenuDir" Name="PathCAM"
+                  WorkingDirectory='INSTALLDIR' Icon="icon.ico" IconIndex="0" Advertise="yes" />
+                <Shortcut Id="desktopPathCAM" Directory="DesktopFolder" Name="PathCAM"
+                  WorkingDirectory='INSTALLDIR' Icon="icon.ico" IconIndex="0" Advertise="yes" />
+              </File>
+			  
+			  <File Id='clipper_libraryDLL' Name='clipper_library.dll' DiskId='1' Source='..\GUI\Bin\Release\clipper_library.dll' />
+			  <File Id='CommandsDLL' Name='Commands.dll' DiskId='1' Source='..\GUI\Bin\Release\Commands.dll' />
+			  <File Id='GCodeDLL' Name='GCode.dll' DiskId='1' Source='..\GUI\Bin\Release\GCode.dll' />
+			  <File Id='GeometryDLL' Name='Geometry.dll' DiskId='1' Source='..\GUI\Bin\Release\Geometry.dll' />
+			  <File Id='OpenTKDLL' Name='OpenTK.dll' DiskId='1' Source='..\GUI\Bin\Release\OpenTK.dll' />
+			  <File Id='OpenTK_GLControlDLL' Name='OpenTK.GLControl.dll' DiskId='1' Source='..\GUI\Bin\Release\OpenTK.GLControl.dll' />
+			  <File Id='QuantumConcepts_CommonDLL' Name='QuantumConcepts.Common.dll' DiskId='1' Source='..\GUI\Bin\Release\QuantumConcepts.Common.dll' />
+			  <File Id='QuantumConcepts_Formats_STLDLL' Name='QuantumConcepts.Formats.STL.dll' DiskId='1' Source='..\GUI\Bin\Release\QuantumConcepts.Formats.STL.dll' />
+			  <File Id='RobotDLL' Name='Robot.dll' DiskId='1' Source='..\GUI\Bin\Release\Robot.dll' />
+			  <File Id='SerialDLL' Name='Serial.dll' DiskId='1' Source='..\GUI\Bin\Release\Serial.dll' />
+			  <File Id='TriangleDLL' Name='Triangle.dll' DiskId='1' Source='..\GUI\Bin\Release\Triangle.dll' />
+			  
+            </Component>
+			
+			
+		  </Directory>
+        <!--/Directory-->
+      </Directory>
+
+      <Directory Id="ProgramMenuFolder" Name="Programs">
+        <Directory Id="ProgramMenuDir" Name="PathCAM">
+          <Component Id="ProgramMenuDir" Guid="2A3E1F52-6D25-4D6C-A610-292FAADF4ABC">
+            <RemoveFolder Id='ProgramMenuDir' On='uninstall' />
+            <RegistryValue Root='HKCU' Key='Software\[Manufacturer]\[ProductName]' Type='string' Value='' KeyPath='yes' />
+          </Component>
+        </Directory>
+      </Directory>
+
+      <Directory Id="DesktopFolder" Name="Desktop" />
+    </Directory>
+	
+	<Feature Id='Complete' Level='1' Title='PathCAM' Description='The PathCAM Software' Display='expand' ConfigurableDirectory='INSTALLDIR'>
+      <ComponentRef Id='MainExecutable' />
+      <ComponentRef Id='ProgramMenuDir' />
+    </Feature>
+	
+	<PropertyRef Id="NETFRAMEWORK45"/>
+	<Condition Message="This application requires .NET Framework 4.5. Please install the .NET Framework then run this installer again.">
+		<![CDATA[Installed OR NETFRAMEWORK45]]>
+	</Condition>
+	
+	<Property Id="WIXUI_INSTALLDIR" Value="INSTALLDIR" />
+	<UI>
+      <UIRef Id="WixUI_InstallDir" />
+
+      <Publish Dialog="WelcomeDlg"
+             Control="Next"
+             Event="NewDialog"
+             Value="InstallDirDlg"
+             Order="2">1</Publish>
+      <Publish Dialog="InstallDirDlg"
+             Control="Back"
+             Event="NewDialog"
+             Value="WelcomeDlg"
+             Order="2">1</Publish>
+    </UI>
+	<UIRef Id="WixUI_ErrorProgressText" />
+	
+	<WixVariable Id="WixUIBannerBmp" Value="banner.bmp" />
+	<WixVariable Id="WixUIDialogBmp" Value="dialog.bmp" />
+	
+	<Icon Id="icon.ico" SourceFile="..\GUI\icon.ico" />
+
+  </Product>
+</Wix>
\ No newline at end of file
diff --git a/Installer/banner.bmp b/Installer/banner.bmp
new file mode 100644
index 0000000..cf12640
Binary files /dev/null and b/Installer/banner.bmp differ
diff --git a/Installer/dialog.bmp b/Installer/dialog.bmp
new file mode 100644
index 0000000..98a0692
Binary files /dev/null and b/Installer/dialog.bmp differ
diff --git a/Installer/readme.txt b/Installer/readme.txt
new file mode 100644
index 0000000..b5ace8d
--- /dev/null
+++ b/Installer/readme.txt
@@ -0,0 +1,10 @@
+You'll need Wix to build the installer:
+
+http://wixtoolset.org/
+
+Make sure the <installdir>\bin directory is in the PATH 
+environment variable.  That allows candle.exe and light.exe 
+to be executed from scripts without providing the full path 
+all the time.
+
+Then just build the VS solution in release mode and double click run.bat
\ No newline at end of file
diff --git a/Installer/run.bat b/Installer/run.bat
new file mode 100644
index 0000000..f3239a4
--- /dev/null
+++ b/Installer/run.bat
@@ -0,0 +1,2 @@
+candle.exe -ext WixNetFxExtension.dll PathCAM.xml
+light.exe -ext WixUIExtension -ext WixNetFxExtension.dll PathCAM.wixobj
\ No newline at end of file