diff --git a/conf/control_panel.xml b/conf/control_panel.xml
index 124d971a9f..6853df4b0b 100644
--- a/conf/control_panel.xml
+++ b/conf/control_panel.xml
@@ -115,7 +115,19 @@
       <program name="map 2d ml"/>
       <program name="messages"><arg flag="-c" constant="telemetry_ap:*"/><arg flag="-c" constant="ground:ground"/></program>
     </session>
-  <session name="display station">
+  <session name="replay">
+<!--      <variable name="ivy_bus" value="192.168.1:2001"/> -->
+      <variable name="map" value="muret_UTM.xml"/>
+      <program name="receive"/>     
+      <program name="http server"/>     
+      <program name="sim"><arg flag="-a" constant="Thon1"/></program>
+      <program name="cockpit"><arg flag="-render" constant="1"/></program>
+      <program name="map 2d ml"/>
+      <program name="play"/>
+    <program name="gaia" command="sw/simulator/gaia"/>
+      <program name="messages"><arg flag="-c" constant="telemetry_ap:*"/><arg flag="-c" constant="ground:ground"/></program>
+    </session>
+ <session name="display station">
       <variable name="ivy_bus" value="192.168.1:2001"/>
       <program name="cockpit"></program>
       <program name="map 2d ml"/>
diff --git a/sw/logalizer/Makefile b/sw/logalizer/Makefile
index 513e4a398b..af65d1be2e 100644
--- a/sw/logalizer/Makefile
+++ b/sw/logalizer/Makefile
@@ -29,7 +29,7 @@ clean:
 	rm -f *.opt *.out *~ core *.o *.bak .depend *.cm* play
 
 play : play.ml
-	$(OCAMLC) -o $@ unix.cma glibivy-ocaml.cma -I +lablgtk2 lablgtk.cma gtkInit.cmo $^ # to check
+	$(OCAMLC) -o $@ unix.cma glibivy-ocaml.cma -I +lablgtk2 -I ../lib/ocaml lablgtk.cma lib-pprz.cma gtkInit.cmo  $^ # to check
 	cat ../../pprz_src_test.sh > $@
-	echo 'exec lablgtk2 unix.cma glibivy-ocaml.cma $$PAPARAZZI_SRC/sw/logalizer/$< $$*' >> $@
+	echo 'exec lablgtk2 unix.cma glibivy-ocaml.cma -I $$PAPARAZZI_SRC/sw/lib/ocaml lib-pprz.cma $$PAPARAZZI_SRC/sw/logalizer/$< $$*' >> $@
 	chmod a+x $@
diff --git a/sw/logalizer/play.ml b/sw/logalizer/play.ml
index b4f8890b81..5c1bf84e1e 100644
--- a/sw/logalizer/play.ml
+++ b/sw/logalizer/play.ml
@@ -1,3 +1,6 @@
+
+module Ground_Pprz = Pprz.Protocol(struct let name = "ground" end)
+
 let log = ref [||]
 
 let load_log = fun window (adj:GData.adjustment) name ->
@@ -80,8 +83,11 @@ let _ =
       ~value:0. ~lower:0. ~upper:1000. 
     ~step_incr:0.5 ~page_incr:1.0 ~page_size:1.0 () in
 
-  let speed = GData.adjustment ~value:1. ~lower:0.05 ~upper:10. 
-    ~step_incr:0.25 ~page_incr:1.0 () in
+(***  let speed = GData.adjustment ~value:1. ~lower:0.05 ~upper:10. 
+    ~step_incr:0.25 ~page_incr:1.0 () in ***)
+
+  let speed = object val mutable v = 1. method value = v method set_value x = v <- x end
+  in
 
   let bus = ref "127.255.255.255:3333" in
   Arg.parse 
@@ -102,11 +108,11 @@ let _ =
   ignore (file_menu_fact#add_item "Quit" ~key:GdkKeysyms._Q ~callback:quit);  
 
 
-  let timescale = GRange.scale `HORIZONTAL ~adjustment:adj ~packing:window#vbox#pack () in
-  let speed_button = GEdit.spin_button ~adjustment:speed ~rate:0. ~digits:2 ~width:50 ~packing:window#vbox#add () in
+ (***) let timescale = GRange.scale `HORIZONTAL ~adjustment:adj ~packing:window#vbox#pack () in
+  let speed_button = GEdit.spin_button (*** ~adjustment:speed ***) ~rate:0. ~digits:2 ~width:50 ~packing:window#vbox#add () in (***)
 
-  (** #move_slider is not working ??? **) ignore (timescale#event#connect#button_release ~callback:(fun _ -> if !was_running then play adj speed; false));
-  ignore (timescale#event#connect#button_press ~callback:(fun _ -> was_running := !timer <> None; stop (); false));
+  (** #move_slider is not working ??? **) (*** ignore (timescale#event#connect#button_release ~callback:(fun _ -> if !was_running then play adj speed; false));
+  ignore (timescale#event#connect#button_press ~callback:(fun _ -> was_running := !timer <> None; stop (); false));  ***)
 
   window#add_accel_group accel_group;
   window#show ();
@@ -114,4 +120,10 @@ let _ =
   Ivy.init "Paparazzi replay" "READY" (fun _ _ -> ());
   Ivy.start !bus;
 
+  let world_update_time = fun _ vs ->
+      speed#set_value (Pprz.float_assoc "time_scale" vs)
+    in
+
+    ignore (Ground_Pprz.message_bind "WORLD_ENV" world_update_time);
+
   GMain.Main.main ()