Rationalized header files:
- mwerks_nonshared_config.h for standalone pythons
- mwerks_shared_config.h for shared pythons (PythonCore, app and
  applet)
- mwerks_plugin_config.h for plugins
Only the _tkinter plugin uses a customized header.

Old config files have gone to the "old" directory, for the time being.
diff --git a/Mac/mwerks/mwerks_nonshared_config.h b/Mac/mwerks/mwerks_nonshared_config.h
index ce93785..cb95b18 100644
--- a/Mac/mwerks/mwerks_nonshared_config.h
+++ b/Mac/mwerks/mwerks_nonshared_config.h
@@ -1,11 +1,20 @@
-#define HAVE_CONFIG_H
-#define USE_STDWIN
-#define USE_MACTCP
-#define USE_BGEN
-#define USE_MACSPEECH
-#define USE_IMG
-#define USE_MACCTB
-#define USE_STACKCHECK
-#ifdef __powerc
-#define USE_MAC_DYNAMIC_LOADING
-#endif
+/*
+** Configuration file for standalone 68k/ppc Python.
+**
+** Note: enabling the switches below is not enough to enable the
+** specific features, you may also need different sets of sources.
+*/
+
+#define USE_GUSI		/* Stdio implemented with GUSI */
+#define USE_TOOLBOX		/* Include toolbox modules in core Python */
+#define USE_QT			/* Include quicktime modules in core Python */
+#define USE_WASTE		/* Include waste module in core Python */
+#define USE_MACSPEECH		/* Include macspeech module in core Python */
+#define USE_IMG	       		/* Include img modules in core Python */
+#define USE_MACCTB		/* Include ctb module in core Python */
+/* #define USE_STDWIN		/* Include stdwin module in core Python */
+/* #define USE_MACTCP		/* Include mactcp (*not* socket) modules in core */
+/* #define USE_TK		/* Include _tkinter module in core Python */
+/* #define MAC_TCL		/* This *must* be on if USE_TK is on */
+/* #define USE_MAC_SHARED_LIBRARY	/* Enable code to add shared-library resources */
+/* #define USE_MAC_APPLET_SUPPORT	/* Enable code to run a PYC resource */
diff --git a/Mac/mwerks/mwerks_plugin_config.h b/Mac/mwerks/mwerks_plugin_config.h
index 519b08b..18d5e67 100644
--- a/Mac/mwerks/mwerks_plugin_config.h
+++ b/Mac/mwerks/mwerks_plugin_config.h
@@ -1 +1,5 @@
-#define HAVE_CONFIG_H
+/*
+** Config file for dynamically-loaded ppc/cfm68k plugin modules.
+*/
+
+#define USE_GUSI		/* Stdio implemented with GUSI */
diff --git a/Mac/mwerks/mwerks_shared_config.h b/Mac/mwerks/mwerks_shared_config.h
index 93aadcd..5bcdeae 100644
--- a/Mac/mwerks/mwerks_shared_config.h
+++ b/Mac/mwerks/mwerks_shared_config.h
@@ -1,6 +1,21 @@
-#define USE_MAC_SHARED_LIBRARY
-#define USE_MAC_APPLET_SUPPORT
-/* #define USE_MACTCP */
-/* #define USE_BGEN */
-/* #define USE_MACSPEECH */
+/*
+** Configuration file for dynamically loaded cfm68k/ppc PythonCore,
+** interpreter and Applet.
+**
+** Note: enabling the switches below is not enough to enable the
+** specific features, you may also need different sets of sources.
+*/
 
+#define USE_GUSI		/* Stdio implemented with GUSI */
+/* #define USE_TOOLBOX		/* Include toolbox modules in core Python */
+/* #define USE_QT		/* Include quicktime modules in core Python */
+/* #define USE_WASTE		/* Include waste module in core Python */
+/* #define USE_MACSPEECH	/* Include macspeech module in core Python */
+/* #define USE_IMG		/* Include img modules in core Python */
+/* #define USE_MACCTB		/* Include ctb module in core Python */
+/* #define USE_STDWIN		/* Include stdwin module in core Python */
+/* #define USE_MACTCP		/* Include mactcp (*not* socket) modules in core */
+/* #define USE_TK		/* Include _tkinter module in core Python */
+/* #define MAC_TCL		/* This *must* be on if USE_TK is on */
+#define USE_MAC_SHARED_LIBRARY		/* Enable code to add shared-library resources */
+#define USE_MAC_APPLET_SUPPORT		/* Enable code to run a PYC resource */
diff --git a/Mac/mwerks/mwerks_tkplugin_config.h b/Mac/mwerks/mwerks_tkplugin_config.h
index 81cd9e8..4b9fdc8 100644
--- a/Mac/mwerks/mwerks_tkplugin_config.h
+++ b/Mac/mwerks/mwerks_tkplugin_config.h
@@ -1,4 +1,7 @@
-#define HAVE_CONFIG_H
-#define USE_TK
-#define MAC_TCL
-#define USE_GUSI
+/*
+** Special config-file for _tkinter plugin.
+*/
+
+#define USE_GUSI		/* Stdio implemented with GUSI */
+#define USE_TK			/* Include _tkinter module in core Python */
+#define MAC_TCL			/* This *must* be on if USE_TK is on */