Added comment about printer resolution, incremented installer version to 2.2.2

Installer/EmbroideryReader.wxs

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
     <!-- ProductGuid should change whenever ProductVersion changes -->
-    <?define ProductVersion="2.2.1" ?>
-    <?define ProductGuid="A199C442-67ED-48C2-946D-437B100693A0" ?>
+    <?define ProductVersion="2.2.2" ?>
+    <?define ProductGuid="{195E5DBD-0A0C-4D34-8018-189B5FDC443A}" ?>
     <Product Id="$(var.ProductGuid)" Name="Embroidery Reader" Language="1033" Version="$(var.ProductVersion)" Manufacturer="Nathan Crawford" UpgradeCode="CE1642E2-5EE0-454F-B7DF-5C9C92D6D40D">
         <Package Description="Test file in a Product" Comments="Simple test" InstallerVersion="200" Compressed="yes" />
         <Media Id="1" Cabinet="simple.cab" EmbedCab="yes" />

embroideryReader/frmMain.cs

@@ -534,7 +534,14 @@ namespace embroideryReader
         {
             if (design != null)
             {
-                // Calculate scale values for print graphics object (100 dpi seems to be the default for the printer graphics object)
+                // Note: scaling based on reported printer DPI may produce terrible results in some
+                // cases. The reported DPI can even be a negative number, which indicates a general print
+                // quality. So, future self, for the sake of your sanity... just don't do it. :-)
+                // See https://msdn.microsoft.com/en-us/library/system.drawing.printing.printerresolution.x(v=vs.110).aspx
+                // for more detail.
+
+                // Calculate scale values for print graphics object (100 dpi seems to be the default
+                // for the printer graphics object)
                 double graphicsXScaleFactor = (100.0 / design.NativeDPI);
                 double graphicsYScaleFactor = (100.0 / design.NativeDPI);