diff --git a/configtool.default.ini b/configtool.default.ini
index 5c887ab..3c09233 100644
--- a/configtool.default.ini
+++ b/configtool.default.ini
@@ -19,11 +19,11 @@ arduinodir =
 #
 # Note: the flag -save-temps=obj does not appear to be a valid flag for win32.
 #       Omit the "=obj", or omit it entirely.
-cflags = -DF_CPU=%F_CPU% -mmcu=%CPU% -Wall -Wstrict-prototypes -std=gnu99
+cflags = -DF_CPU=%%F_CPU%% -mmcu=%%CPU%% -Wall -Wstrict-prototypes -std=gnu99
          -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
          -Winline -fno-move-loop-invariants -fno-tree-scev-cprop -Os
          -ffunction-sections -finline-functions-called-once -mcall-prologues
-         -Wa,-adhlns=%ALNAME% -save-temps=obj
+         -Wa,-adhlns=%%ALNAME%% -save-temps=obj
 
 # Flags passed to avr-gcc to be passed on to the linker.
 ldflags = -Wl,--as-needed -Wl,--gc-sections
diff --git a/configtool/build.py b/configtool/build.py
index f2092a5..e31b31f 100644
--- a/configtool/build.py
+++ b/configtool/build.py
@@ -1,11 +1,18 @@
 import wx.lib.newevent
-import thread, shlex, subprocess
-import os, re
+
+try:
+    import thread as _thread
+except ImportError:
+    import _thread
+import shlex
+import subprocess
+import os
+import re
 from os.path import isfile, join
 from sys import platform
 
 if platform.startswith("win"):
-    from _subprocess import STARTF_USESHOWWINDOW
+    from subprocess import STARTF_USESHOWWINDOW
 
 (scriptEvent, EVT_SCRIPT_UPDATE) = wx.lib.newevent.NewEvent()
 SCRIPT_RUNNING = 1
@@ -80,7 +87,7 @@ class ScriptThread:
     def Start(self):
         self.running = True
         self.cancelled = False
-        thread.start_new_thread(self.Run, ())
+        _thread.start_new_thread(self.Run, ())
 
     def Stop(self):
         self.cancelled = True