diff --git a/automaton.c b/automaton.c
index 3de81f4..4f4f6fa 100644
--- a/automaton.c
+++ b/automaton.c
@@ -16,18 +16,18 @@ static int choice_STATE_RULES_DATA = STATE;
 /*                          T R A N S I T I O N S                             */
 /******************************************************************************/
 
-void debug_printing (int prescribed, int sub_automaton);
+static void debug_printing (int prescribed, int sub_automaton);
 
 void set_EXEC_EDIT (int prescribed) {
   if (choice_EXEC_EDIT != prescribed) {
-    debug_printing (prescribed, 0);
+    debug_printing (prescribed, 0); // EXEC_EDIT is sub_automaton 0
     choice_EXEC_EDIT = prescribed;
   }
 }
 
 void set_STATE_RULES_DATA (int prescribed) {
   if (choice_STATE_RULES_DATA != prescribed) {
-    debug_printing (prescribed, 1);
+    debug_printing (prescribed, 1); // STATE_RULES_DATA is sub_automaton 1
     choice_STATE_RULES_DATA = prescribed;
   }
 }
@@ -40,7 +40,7 @@ void set_STATE_RULES_DATA (int prescribed) {
 int  get_EXEC_EDIT () {return choice_EXEC_EDIT;}
 int  get_STATE_RULES_DATA () {return choice_STATE_RULES_DATA;}
 
-char *get_str_EXEC_EDIT (int value) {
+static char *get_str_EXEC_EDIT (int value) {
   switch (value) {
   case (EXEC) : return "EXEC";
   case (EDIT) : return "EDIT";
@@ -48,7 +48,7 @@ char *get_str_EXEC_EDIT (int value) {
   }
 }
 
-char *get_str_STATE_RULES_DATA (int value) {
+static char *get_str_STATE_RULES_DATA (int value) {
  switch (value) {
   case (STATE) : return "STATE";
   case (RULES) : return "RULES";
@@ -57,8 +57,9 @@ char *get_str_STATE_RULES_DATA (int value) {
  }
 }
 
-void debug_printing (int prescribed, int sub_automaton) {
-  switch (sub_automaton) {
+static void debug_printing (int prescribed, int sub_automaton) {
+  switch (sub_automaton) { // sub_automaton 0 is EXEC_EDIT and
+                           // sub_automaton 1 is STATE_RULES_DATA
   case (0) :  printf("switch >   %5s  X  %5s   <>   %5s  X  %5s\n",
            get_str_EXEC_EDIT (choice_EXEC_EDIT),
            get_str_STATE_RULES_DATA (choice_STATE_RULES_DATA),
diff --git a/automaton.h b/automaton.h
index 8126494..48e5517 100644
--- a/automaton.h
+++ b/automaton.h
@@ -11,6 +11,6 @@ void set_STATE_RULES_DATA (int prescribed);
 int  get_EXEC_EDIT ();
 int  get_STATE_RULES_DATA ();
 
-char *get_str_EXEC_EDIT (int value);
-char *get_str_STATE_RULES_DATA (int value);
+// char *get_str_EXEC_EDIT (int value);
+// char *get_str_STATE_RULES_DATA (int value);
 
diff --git a/callback.c b/callback.c
index e164bc6..f42cd4a 100644
--- a/callback.c
+++ b/callback.c
@@ -167,21 +167,21 @@ void on_axis_value_change(GtkAdjustment *adjustment, gpointer data)
 /*                             B U T T O N S                                  */
 /******************************************************************************/
 
-/*void on_toggle_MODEL_RUN_STOP (GtkWidget *btt_MODEL_RUN_STOP, gpointer data) {
-  if (strcmp (gtk_button_get_label (GTK_BUTTON (btt_MODEL_RUN_STOP)), "  run  "))
-       gtk_button_set_label (GTK_BUTTON (btt_MODEL_RUN_STOP), "  run  ");
-  else gtk_button_set_label (GTK_BUTTON (btt_MODEL_RUN_STOP), " stop ");}*/
+void on_toggle_EXEC_EDIT (GtkWidget *toggled_button, gpointer user_data) {
 
-void on_toggle_EXEC_EDIT
-(GtkWidget *btt_XOR_EXEC_EDIT, gpointer user_data) {
-  if (get_EXEC_EDIT ()) {//  (strcmp (get_str_EXEC_EDIT(0), "EXEC")) {
-    gtk_button_set_icon_name (GTK_BUTTON (btt_XOR_EXEC_EDIT), "power-profile-balanced-rtl-symbolic");
+  if (get_EXEC_EDIT ()) {
+    gtk_button_set_icon_name (GTK_BUTTON (toggled_button), "power-profile-balanced-rtl-symbolic");
     set_EXEC_EDIT (EXEC);
   } else {
-  //  gtk_button_set_icon_name (GTK_BUTTON (btt_XOR_EXEC_EDIT), "preferences-system-symbolic");
-    gtk_button_set_icon_name (GTK_BUTTON (btt_XOR_EXEC_EDIT), "text-editor-symbolic");
+    gtk_button_set_icon_name (GTK_BUTTON (toggled_button), "text-editor-symbolic");
     set_EXEC_EDIT (EDIT);
   }
+  switch (get_STATE_RULES_DATA()) {
+    case (STATE) : gtk_window_set_child (main_window, GTK_WIDGET (get_window_child_STATE())); break;
+    case (RULES) : gtk_window_set_child (main_window, GTK_WIDGET (get_window_child_RULES())); break;
+    case (DATA)  : gtk_window_set_child (main_window, GTK_WIDGET (get_window_child_DATA()));  break;
+    default :  printf("default in callback.on_toggle_STATE_RULES_DATA()\n");
+  }
 }
 
 void on_toggle_STATE_RULES_DATA (GtkWidget *toggled_button, gpointer user_data) {
diff --git a/contain.c b/contain.c
index 7d722e8..3f0a463 100644
--- a/contain.c
+++ b/contain.c
@@ -236,7 +236,8 @@ GtkWidget *get_window_child_STATE() {
     gtk_box_append (page_box, GTK_WIDGET (gtk_separator_new (GTK_ORIENTATION_HORIZONTAL)));
     gtk_box_append (page_box, GTK_WIDGET (get_SPACE_VIEW_box()));
     gtk_box_append (page_box, GTK_WIDGET (gtk_separator_new (GTK_ORIENTATION_HORIZONTAL)));
-    gtk_box_append (page_box, GTK_WIDGET (get_TIME_EXEC_controls_box()));
+    if (get_EXEC_EDIT ()) gtk_box_append (page_box, GTK_WIDGET (get_SPACE_EDIT_controls_box()));
+    else                  gtk_box_append (page_box, GTK_WIDGET (get_TIME_EXEC_controls_box()));
     return GTK_WIDGET (page_box);
 }