diff --git a/callback.c b/callback.c
index e3a7199..a52e36e 100644
--- a/callback.c
+++ b/callback.c
@@ -160,58 +160,30 @@ void on_axis_value_change(GtkAdjustment *adjustment, gpointer data)
 /******************************************************************************/
 void on_toggle_exec_edit (GtkWidget *btt_exec_xor_edit, GtkWidget *btt_run_stop_model_exec)
 {
-  if (get_status()) {
-    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "power-profile-balanced-rtl-symbolic");
-    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), " run ");
-    gtk_widget_set_sensitive (GTK_WIDGET (btt_run_stop_model_exec), TRUE);
-    set_status (0);
-  } else {
-    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "document-edit-symbolic");
-    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "text-editor-symbolic"); // I hesitate
-    set_status (1);
-    //   Ici, il faudra prévenir l'utilisateur par une pop-up window :   TODO   (sauvegarde automatique sinon)
-    //   S'il ne prend pas la main, les données de la simulation en cours risquent d'être perdues
-    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), "  off ");
-    gtk_widget_set_sensitive (GTK_WIDGET (btt_run_stop_model_exec), FALSE);
-    set_status (0);
-  }
+//    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "power-profile-balanced-rtl-symbolic");
+//    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), " run ");
+//    gtk_widget_set_sensitive (GTK_WIDGET (btt_run_stop_model_exec), TRUE);
+
+//    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "document-edit-symbolic");
+//    gtk_button_set_icon_name (GTK_BUTTON (btt_exec_xor_edit), "text-editor-symbolic"); // I hesitate
+//    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), "  off ");
+//    gtk_widget_set_sensitive (GTK_WIDGET (btt_run_stop_model_exec), FALSE);
 }
 
 void on_toggle_model_exec (GtkWidget *btt_run_stop_model_exec, gpointer data)
 {
-  if (get_status() && ! get_status()) {
-    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), " run ");
-    set_status (0);
-  } else {
-    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), "stop");
-    set_status (1);
-  }
+//    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), " run ");
+//    gtk_button_set_label (GTK_BUTTON (btt_run_stop_model_exec), "stop");
 }
 
-//  in_depth.c :  enum { STATE, RULES, MEASURE, OBSERVE, INTERPRET, HELP, CONFIGURE };
-
 void on_toggle_state_rules (GtkWidget *btt_toggle_state_rules, gpointer data)
 {
-  if (get_status()) {
-    gtk_button_set_label (GTK_BUTTON (btt_toggle_state_rules), "state");
-    window_main_child (main_window, 0); //  0 = state page (see contain.c)
-    set_status (0);
-  } else {
-    gtk_button_set_label (GTK_BUTTON (btt_toggle_state_rules), "rules");
-    window_main_child (main_window, 1); //  1 = rules page (see contain.c)
-    set_status (1);
-  }
+//    gtk_button_set_label (GTK_BUTTON (btt_toggle_state_rules), "state");
+//    gtk_button_set_label (GTK_BUTTON (btt_toggle_state_rules), "rules");
 }
 
 void on_toggle_observ_interpret (GtkWidget *btt_toggle_observ_interpret, gpointer data)
 {
-  if (get_status()) {
-    gtk_button_set_label (GTK_BUTTON (btt_toggle_observ_interpret), "observe");
-    window_main_child (main_window, 2); //  2 = measures page (see contain.c)
-    set_status (0);
-  } else {
-    gtk_button_set_label (GTK_BUTTON (btt_toggle_observ_interpret), "interpret");
-    window_main_child (main_window, 3); //  3 = observe page (see contain.c)
-    set_status (1);
-  }
+//    gtk_button_set_label (GTK_BUTTON (btt_toggle_observ_interpret), "observe");
+//    gtk_button_set_label (GTK_BUTTON (btt_toggle_observ_interpret), "interpret");
 }
diff --git a/contain.c b/contain.c
index bcb36f3..db53237 100644
--- a/contain.c
+++ b/contain.c
@@ -148,8 +148,8 @@ GtkWidget *get_SPACE_EDIT_controls_box() {
 
 
 void window_main_child_bottom (GtkBox *page_box){
-    if (! get_status ())    gtk_box_append (page_box, GTK_WIDGET (get_TIME_EXEC_controls_box()));
-    else                    gtk_box_append (page_box, GTK_WIDGET (get_SPACE_EDIT_controls_box()));
+    // gtk_box_append (page_box, GTK_WIDGET (get_TIME_EXEC_controls_box()));
+    // gtk_box_append (page_box, GTK_WIDGET (get_SPACE_EDIT_controls_box()));
 }
 
 static void icons_for_fun (GtkHeaderBar *header_bar);
diff --git a/in_depth.c b/in_depth.c
index bf952f8..7932ed9 100644
--- a/in_depth.c
+++ b/in_depth.c
@@ -9,7 +9,7 @@
 
 // (exec / edit) X (state / rules / measure) X (observ / interpret / read / write)
 
-enum {
+enum {  //  S T A T E S
   EXEC_STOP,
   EXEC_RUN,
   EXEC_STOP_EDIT_RULE,
@@ -24,49 +24,77 @@ enum {
   CONFIGURE
 };
 
-static int status = EXEC_STOP;
-int  get_status () {return status;}
+static int status = EXEC_STOP; // int  get_status () {return status;}
 
+enum {  //  T R A N S I T I O N S
+  EXEC_TO_RUN,
+  RUN_TO_EXEC,
+};
 /******************************************************************************/
 /*                          T R A N S I T I O N S                             */
 /******************************************************************************/
 
-void set_status (int prescribed) {
-  status = prescribed;   if (0) printf ("status = %d\n", status);
-
-  switch (status) {
-  case (0) :  /*  EXEC_STOP  */
+void let_transition_be (int asked) {
+  switch (asked) {
+  case (0) :  //  EXEC_TO_RUN
     status = EXEC_RUN;
     break;
-  case (1) :  /*  EXEC_RUN  */
+  case (1) :  //  RUN_TO_EXEC
+    //   Ici, il faudra prévenir l'utilisateur par une pop-up window :   TODO   (sauvegarde automatique sinon)
+    //   S'il ne prend pas la main, les données de la simulation en cours risquent d'être perdues
     status = EXEC_STOP;
     break;
-  case (2) :  /*  EXEC_STOP_EDIT_STOP  */
-    status = EXEC_RUN_EDIT_RULE;
-    break;
-  case (3) :  /*  EXEC_RUN_EDIT_RULE  */
-    status = EXEC_STOP_EDIT_RULE;
-    break;
-  case (4) :  /*  EXEC_STOP_EDIT_MEASURE  */
-    status = EXEC_RUN_EDIT_MEASURE;
-    break;
-  case (5) :  /*  EXEC_RUN_EDIT_MEASURE  */
-    status = EXEC_STOP_EDIT_MEASURE;
-    break;
-  case (6) :  /*  EDIT_STATE  */
-    break;
-  case (7) :  /*  EDIT_RULE  */
-    break;
-  case (8) :  /*  OBSERVE  */
-    break;
-  case (9) :  /*  INTERPRET  */
-    break;
-  case (10) :  /*  HELP  */
-    break;
-  case (11) :  /*  CONFIGURE  */
-    break;
-  case (12) :  /*  OTHER  */
-    break;
   default : ;
   }
 }
+
+
+
+
+
+
+
+
+
+/*
+void set_status (int prescribed) {
+  status = prescribed;   if (0) printf ("status = %d\n", status);
+
+  switch (status) {
+  case (0) :  //  EXEC_STOP
+    status = EXEC_RUN;
+    break;
+  case (1) :  //  EXEC_RUN
+    //   Ici, il faudra prévenir l'utilisateur par une pop-up window :   TODO   (sauvegarde automatique sinon)
+    //   S'il ne prend pas la main, les données de la simulation en cours risquent d'être perdues
+    status = EXEC_STOP;
+    break;
+  case (2) :  //  EXEC_STOP_EDIT_STOP
+    status = EXEC_RUN_EDIT_RULE;
+    break;
+  case (3) :  //  EXEC_RUN_EDIT_RULE
+    status = EXEC_STOP_EDIT_RULE;
+    break;
+  case (4) :  //  EXEC_STOP_EDIT_MEASURE
+    status = EXEC_RUN_EDIT_MEASURE;
+    break;
+  case (5) :  //  EXEC_RUN_EDIT_MEASURE
+    status = EXEC_STOP_EDIT_MEASURE;
+    break;
+  case (6) :  //  EDIT_STATE
+    break;
+  case (7) :  //  EDIT_RULE
+    break;
+  case (8) :  //  OBSERVE
+    break;
+  case (9) :  //  INTERPRET
+    break;
+  case (10) :  //  HELP
+    break;
+  case (11) :  //  CONFIGURE
+    break;
+  case (12) :  //  OTHER
+    break;
+  default : ;
+  }
+} */