diff --git a/src/fileformats.c b/src/fileformats.c
index 02c52a78..70c0be90 100644
--- a/src/fileformats.c
+++ b/src/fileformats.c
@@ -2636,8 +2636,10 @@ void Save_GIF(T_IO_Context * context)
             if (context->Type == CONTEXT_MAIN_IMAGE && Main_backups->Pages->Image_mode == IMAGE_MODE_ANIMATION)
             {
               // Animation frame
+              int duration;
               GCE.Packed_fields=(2<<2)|(context->Background_transparent);
-              GCE.Delay_time=Get_frame_duration(context)/10;
+              duration=Get_frame_duration(context)/10;
+              GCE.Delay_time=duration<0xFFFF?duration:0xFFFF;
             }
             else
             {
diff --git a/src/init.c b/src/init.c
index 9fcdd3fa..f9887f41 100644
--- a/src/init.c
+++ b/src/init.c
@@ -1308,7 +1308,7 @@ void Init_buttons(void)
               Do_nothing,
               FAMILY_INSTANT);
   Init_button(BUTTON_ANIM_PREV_FRAME,
-              "Go to previous frame    ",
+              "Go to prev. frame/Rewind",
               130,0,
               13,13,
               BUTTON_SHAPE_RECTANGLE,
@@ -1317,7 +1317,7 @@ void Init_buttons(void)
               Do_nothing,
               FAMILY_INSTANT);
   Init_button(BUTTON_ANIM_NEXT_FRAME,
-              "Go to next frame        ",
+              "Go to next frame / Play ",
               144,0,
               13,13,
               BUTTON_SHAPE_RECTANGLE,
diff --git a/src/layers.c b/src/layers.c
index 3057ba33..77c5939b 100644
--- a/src/layers.c
+++ b/src/layers.c
@@ -436,16 +436,16 @@ void Button_Anim_time(void)
   short clicked_button;
   int mode=0;
   int frame;
-  char buffer[5+1];
+  char buffer[6+1];
   T_Special_button * input_duration_button;
   int duration=Main_backups->Pages->Image[Main_current_layer].Duration;
   
   Open_window(166,110,"Animation speed");
 
-  Print_in_window(80,20,"ms",MC_Black,MC_Light);
-  input_duration_button = Window_set_input_button(33,18,5); // 1
+  Print_in_window(88,20,"ms",MC_Black,MC_Light);
+  input_duration_button = Window_set_input_button(33,18,6); // 1
 
-  Num2str(duration,buffer,5);
+  Num2str(duration,buffer,6);
   Print_in_window_limited(input_duration_button->Pos_X+2,input_duration_button->Pos_Y+2,buffer,input_duration_button->Width/8,MC_Black,MC_Light);
   
   Print_in_window(24,37,"Set this frame",MC_Black,MC_Light);
@@ -472,12 +472,18 @@ void Button_Anim_time(void)
     switch(clicked_button)
     {
       case 1: // duration
-        Num2str(duration,buffer,5);
+        // safety
+        if (duration <= -10000)
+          sprintf(buffer,"-99999");
+        else if (duration >= 1000000)
+          sprintf(buffer,"999999");
+        else
+          sprintf(buffer,"%d", duration);
         Hide_cursor();
         if (Readline(input_duration_button->Pos_X+2, 
           input_duration_button->Pos_Y+2,
           buffer,
-          5,
+          6,
           INPUT_TYPE_DECIMAL))
         {
           duration=atoi(buffer);
@@ -509,13 +515,17 @@ void Button_Anim_time(void)
     switch(mode)
     {
       case 0:
-        if (duration<1)
-          duration=1;
+        if (duration<0)
+          duration=0;
+        else if (duration>655350)
+          duration=655350;
         Main_backups->Pages->Image[Main_current_layer].Duration = duration;
         break;
       case 1:
-        if (duration<1)
-          duration=1;
+        if (duration<0)
+          duration=0;
+        else if (duration>655350)
+          duration=655350;
         for (frame=0; frame<Main_backups->Pages->Nb_layers; frame++)
         {
           Main_backups->Pages->Image[frame].Duration = duration;
@@ -525,10 +535,10 @@ void Button_Anim_time(void)
         for (frame=0; frame<Main_backups->Pages->Nb_layers; frame++)
         {
           int cur_duration = Main_backups->Pages->Image[frame].Duration+duration;
-          if (cur_duration<1)
-            cur_duration=1;
-          else if (cur_duration>32767)
-            cur_duration=32767;
+          if (cur_duration<0)
+            cur_duration=0;
+          else if (cur_duration>655350)
+            cur_duration=655350;
           Main_backups->Pages->Image[frame].Duration = cur_duration;
         }
         break;
diff --git a/src/pages.c b/src/pages.c
index 0f235092..3779af48 100644
--- a/src/pages.c
+++ b/src/pages.c
@@ -67,7 +67,7 @@ T_Page * New_page(int nb_layers)
     for (i=0; i<nb_layers; i++)
     {
       page->Image[i].Pixels=NULL;
-      page->Image[i].Duration=1;
+      page->Image[i].Duration=100;
     }
     page->Width=0;
     page->Height=0;
@@ -445,7 +445,7 @@ void Clear_page(T_Page * page)
   {
     Free_layer(page, i);
     page->Image[i].Pixels=NULL;
-    page->Image[i].Duration=1;
+    page->Image[i].Duration=0;
   }
 
   // Free_gradient() : This data is reference-counted
@@ -1319,6 +1319,7 @@ byte Add_layer(T_List_of_pages *list, int layer)
   T_Page * new_page;
   byte * new_image;
   int i;
+  int duration;
   
   source_page = list->Pages;
   
@@ -1359,7 +1360,13 @@ byte Add_layer(T_List_of_pages *list, int layer)
     new_page->Image[i]=new_page->Image[i-1];
   }
   new_page->Image[layer].Pixels=new_image;
-  new_page->Image[layer].Duration=1;
+  if (list->Pages->Nb_layers==0)
+    duration=100;
+  else if (layer>0)
+    duration=new_page->Image[layer-1].Duration;
+  else
+    duration=new_page->Image[1].Duration;
+  new_page->Image[layer].Duration=duration;
   // Fill with transparency, initially
   memset(new_image, Main_backups->Pages->Transparent_color, list->Pages->Height*list->Pages->Width); // transparent color