A few missing casts (Richard Neitzel).
Don't append Unix paths on a Mac (Jack Jansen).
diff --git a/Tools/modulator/modulator.py b/Tools/modulator/modulator.py
index dd1ade5..02ad80d 100755
--- a/Tools/modulator/modulator.py
+++ b/Tools/modulator/modulator.py
@@ -17,7 +17,8 @@
 #
 
 import sys, os
-sys.path.append(os.path.join(os.environ['HOME'], 'src/python/Tools/modulator'))
+if os.name <> 'mac':
+	sys.path.append(os.path.join(os.environ['HOME'], 'src/python/Tools/modulator'))
 
 from Tkinter import *
 from Tkextra import *