Added comment for non-obvious code, fixed option name in nib2cib

AppKit/CPFont.j

@@ -311,6 +311,7 @@ var CPFontNameKey     = @"CPFontNameKey",
         isBold = [aCoder decodeBoolForKey:CPFontIsBoldKey],
         isItalic = [aCoder decodeBoolForKey:CPFontIsItalicKey];
 
+    // Substitute configured font for legacy font
     if (fontName === _CPFontDefaultSystemFontFace && _CPFontDefaultSystemFontFace !== _CPFontSystemFontFace)
     {
         fontName = _CPFontSystemFontFace;

Tools/nib2cib/main.j

@@ -54,7 +54,7 @@ parser.option("--mac", "format")
     .def(NibFormatUndetermined)
     .help("Set format to Mac");
 
-parser.option("--legacy", "conversionMode")
+parser.option("--legacy", "layoutMode")
     .set(ConverterModeLegacy)
     .def(ConverterModeNew)
     .help("Use legacy code that does not preserve view positioning/sizing");