diff --git a/Makefile b/Makefile
index cf9e41e6..0a53b610 100644
--- a/Makefile
+++ b/Makefile
@@ -27,6 +27,7 @@
   datarootdir = $(prefix)/share
   datadir = $(datarootdir)
 
+# Compile with OPTIM=0 to disable gcc optimizations, to enable debug.
   STRIP = strip
 
 
@@ -40,7 +41,7 @@ ifdef COMSPEC
   RMDIR = rmdir
   CP = cp
   BIN = grafx2.exe
-  COPT = -W -Wall -Wdeclaration-after-statement -O -g -ggdb `sdl-config --cflags` $(TTFCOPT) $(JOYCOPT)
+  COPT = -W -Wall -Wdeclaration-after-statement -O$(OPTIM) -g -ggdb `sdl-config --cflags` $(TTFCOPT) $(JOYCOPT)
   LOPT = `sdl-config --libs` -lSDL_image $(TTFLOPT) -lpng
   CC = gcc
   OBJDIR = obj/win32
@@ -177,7 +178,7 @@ else
         #cross compile a Win32 executable
         CC = i586-mingw32msvc-gcc
         BIN = grafx2.exe
-        COPT = -W -Wall -Wdeclaration-after-statement -O -g -ggdb -Dmain=SDL_main `/usr/local/cross-tools/i386-mingw32/bin/sdl-config --cflags` $(TTFCOPT)
+        COPT = -W -Wall -Wdeclaration-after-statement -O$(OPTIM) -g -ggdb -Dmain=SDL_main `/usr/local/cross-tools/i386-mingw32/bin/sdl-config --cflags` $(TTFCOPT)
         LOPT = -mwindows -lmingw32 -lSDLmain -lSDL -lshlwapi `/usr/local/cross-tools/i386-mingw32/bin/sdl-config --libs` -lSDL_image $(TTFLOPT)
         OBJDIR = obj/win32
         PLATFORM = win32
@@ -197,7 +198,7 @@ else
         # Compiles a regular linux exectutable for the native platform
         BIN = grafx2
         COPT = -W -Wall -Wdeclaration-after-statement -pedantic -std=c99 -c -g `sdl-config --cflags` $(TTFCOPT)
-        LOPT = `sdl-config --libs` -lSDL_image $(TTFLOPT)
+        LOPT = `sdl-config --libs` -lSDL_image $(TTFLOPT) -lpng
         CC = gcc
         OBJDIR = obj/unix
         X11LOPT = -lX11
diff --git a/buttons.c b/buttons.c
index 205efb10..b9dd4847 100644
--- a/buttons.c
+++ b/buttons.c
@@ -1673,8 +1673,6 @@ void Button_Safety_resolution(void)
   Unselect_bouton(BUTTON_MAGNIFIER);
   Init_mode_video(640, 400, 0,PIXEL_SIMPLE);
   Current_resolution=0;
-  Video_mode[0].Width = Screen_width*Pixel_width;
-  Video_mode[0].Height = Screen_height*Pixel_height;
   Display_menu();
   Display_all_screen();
 
diff --git a/engine.c b/engine.c
index a8e2074c..c2bd1c81 100644
--- a/engine.c
+++ b/engine.c
@@ -524,8 +524,6 @@ void Main_handler(void)
     {
       Hide_cursor();
       Init_mode_video(Resize_width, Resize_height, 0, Pixel_ratio);
-      Video_mode[0].Width = Screen_width*Pixel_width;
-      Video_mode[0].Height = Screen_height*Pixel_height;
       // Remise à zero des variables indiquant le Redimensionnement demandé
       Display_menu();
       Display_all_screen();
diff --git a/graph.c b/graph.c
index f5cc2afd..1905d44f 100644
--- a/graph.c
+++ b/graph.c
@@ -190,6 +190,9 @@ int Init_mode_video(int width, int height, int fullscreen, int pix_ratio)
   int pix_height;
   byte screen_changed;
   byte pixels_changed;
+  int absolute_mouse_x=Mouse_X*Pixel_width;
+  int absolute_mouse_y=Mouse_Y*Pixel_height;
+  
   
   switch (pix_ratio)
   {
@@ -212,13 +215,26 @@ int Init_mode_video(int width, int height, int fullscreen, int pix_ratio)
       break;
   }
 
+  screen_changed = (Screen_width*Pixel_width!=width ||
+                    Screen_height*Pixel_height!=height ||
+                    Video_mode[Current_resolution].Fullscreen != fullscreen);
+
   // Valeurs raisonnables: minimum 320x200
   if (!fullscreen)
   {
     if (width < 320*pix_width)
+    {
         width = 320*pix_width;
+        screen_changed=1;
+    }
     if (height < 200*pix_height)
+    {
         height = 200*pix_height;
+        screen_changed=1;
+    }
+    Video_mode[0].Width = width;
+    Video_mode[0].Height = height;
+
   }
   else
   {
@@ -233,9 +249,6 @@ int Init_mode_video(int width, int height, int fullscreen, int pix_ratio)
       width = (width + 3 ) & 0xFFFFFFFC;
   #endif  
 
-  screen_changed = (Screen_width*Pixel_width!=width ||
-                    Screen_height*Pixel_height!=height ||
-                    Video_mode[Current_resolution].Fullscreen != fullscreen);
   pixels_changed = (Pixel_ratio!=pix_ratio);
   
   if (!screen_changed && !pixels_changed)
@@ -405,6 +418,14 @@ int Init_mode_video(int width, int height, int fullscreen, int pix_ratio)
   y_sensitivity>>=Mouse_fix_factor_Y;
   Mouse_sensitivity(x_sensitivity?x_sensitivity:1,y_sensitivity?y_sensitivity:1);
 
+  Mouse_X=absolute_mouse_x/Pixel_width;
+  if (Mouse_X>=Screen_width)
+    Mouse_X=Screen_width-1;
+  Mouse_Y=absolute_mouse_y/Pixel_height;
+  if (Mouse_Y>=Screen_height)
+    Mouse_Y=Screen_height-1;
+  Set_mouse_position();
+  
   Spare_offset_X=0; // |  Il faut penser à éviter les incohérences
   Spare_offset_Y=0; // |- de décalage du brouillon par rapport à
   Spare_magnifier_mode=0; // |  la résolution.
diff --git a/loadsave.c b/loadsave.c
index d5fd7bbe..73f01154 100644
--- a/loadsave.c
+++ b/loadsave.c
@@ -514,7 +514,8 @@ void filename_complet(char * filename, byte is_colorix_format)
 void Read_one_byte(FILE * file, byte *b)
 {
   // FIXME : Replace les appelants par Read_bytes(), et gérer les retours d'erreur.
-  Read_byte(file, b);
+  if (!Read_byte(file, b))
+    File_error=2;
 }
 
 // --------------------------------------------------------------------------
@@ -645,6 +646,16 @@ void Load_image(byte image)
     {
       if ( (File_error!=1) && (File_formats[format].Backup_done) )
       {
+        if (Pixel_load_function==Pixel_load_in_preview)
+        {
+          dword  color_usage[256];
+          Count_used_colors_area(color_usage,Preview_pos_X,Preview_pos_Y,Main_image_width/Preview_factor_X,Main_image_height/Preview_factor_Y);
+          //Count_used_colors(color_usage);
+          Display_cursor();
+          Set_nice_menu_colors(color_usage,1);
+          Hide_cursor();
+        }
+      
         // On considère que l'image chargée n'est plus modifiée
         Main_image_is_modified=0;
         // Et on documente la variable Main_fileformat avec la valeur:
diff --git a/misc.c b/misc.c
index 31103d3a..ca599ccc 100644
--- a/misc.c
+++ b/misc.c
@@ -40,7 +40,7 @@
 word Count_used_colors(dword* usage)
 {
   int nb_pixels=0;
-  Uint8* Pixel_Courant=Main_screen;
+  Uint8* current_pixel=Main_screen;
   Uint8 color;
   word nb_colors=0;
   int i;
@@ -53,12 +53,12 @@ word Count_used_colors(dword* usage)
   // On parcourt l'écran courant pour compter les utilisations des couleurs
   for(i=0;i<nb_pixels;i++)
   {
-    color=*Pixel_Courant; //on lit la couleur dans l'écran
+    color=*current_pixel; //on lit la couleur dans l'écran
 
     usage[color]++; //Un point de plus pour cette couleur
 
     // On passe au pixel suivant
-    Pixel_Courant++;
+    current_pixel++;
   }
 
   //On va maintenant compter dans la table les couleurs utilisées:
@@ -71,6 +71,36 @@ word Count_used_colors(dword* usage)
   return nb_colors;
 }
 
+/// Same as ::Count_used_colors, but for a given rectangle.
+word Count_used_colors_area(dword* usage, word start_x, word start_y, word width, word height)
+{
+  Uint8 color;
+  word x,y;
+  word nb_colors=0;
+  int i;
+
+  // Init usage table
+  for (i=0;i<256;i++) usage[i]=0;
+
+  // On parcourt l'écran courant pour compter les utilisations des couleurs
+  for(y=0;y<height;y++)
+  {
+    for(x=0;x<width;x++)
+    {
+      color=*(Screen_pixels+((start_x+x)+(start_y+y)*Screen_width*Pixel_height)*Pixel_width); //on lit la couleur dans l'écran
+      usage[color]++; //Un point de plus pour cette couleur
+    }
+  }
+  //On va maintenant compter dans la table les couleurs utilisées:
+  for(i=0;i<256;i++)
+  {
+    if (usage[i]!=0)
+        nb_colors++;
+  }
+  return nb_colors;
+}
+
+
 void Set_palette(T_Palette palette)
 {
   register int i;
diff --git a/misc.h b/misc.h
index 7e510863..47898cc5 100644
--- a/misc.h
+++ b/misc.h
@@ -38,7 +38,7 @@ void Wait_VBL(void);
 void Slider_timer(byte speed);
 dword Round_div(dword numerator,dword divisor);
 word Count_used_colors(dword * usage);
-
+word Count_used_colors_area(dword* usage, word start_x, word start_y, word width, word height);
 void Pixel_in_current_screen      (word x,word y,byte color);
 void Pixel_in_brush             (word x,word y,byte color);
 byte Read_pixel_from_current_screen  (word x,word y);
diff --git a/palette.c b/palette.c
index 6d294157..a7944c61 100644
--- a/palette.c
+++ b/palette.c
@@ -385,7 +385,7 @@ void Swap(int with_remap,short block_1_start,short block_2_start,short block_siz
 
 
 
-void Set_nice_menu_colors(dword * color_usage)
+void Set_nice_menu_colors(dword * color_usage,int not_picture)
 {
   short index,index2;
   byte color;
@@ -445,8 +445,16 @@ void Set_nice_menu_colors(dword * color_usage)
     replace_table[new_colors[index]]=Best_color_nonexcluded
                                   (rgb[index].R,rgb[index].G,rgb[index].B);
 
-  // On fait un changement des couleurs visibles à l'écran et dans l'image
-  Remap_image_highlevel(replace_table);
+  if (not_picture)
+  {
+    // Remap caused by preview. Only remap screen
+    Remap_zone_highlevel(0,0,Screen_width,Screen_height,replace_table);
+  }
+  else
+  {
+    // On fait un changement des couleurs visibles à l'écran et dans l'image
+    Remap_image_highlevel(replace_table);
+  }
   Display_cursor();
 }
 
@@ -1398,7 +1406,7 @@ void Button_Palette(void)
         {
           memcpy(temp_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,working_palette,sizeof(T_Palette));
-          Set_nice_menu_colors(color_usage);
+          Set_nice_menu_colors(color_usage,0);
           memcpy(working_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,temp_palette,sizeof(T_Palette));
         }
@@ -1444,7 +1452,7 @@ void Button_Palette(void)
         {
           memcpy(temp_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,working_palette,sizeof(T_Palette));
-          Set_nice_menu_colors(color_usage);
+          Set_nice_menu_colors(color_usage,0);
           memcpy(working_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,temp_palette,sizeof(T_Palette));
         }
@@ -1946,7 +1954,7 @@ void Button_Palette(void)
           memcpy(backup_palette,working_palette,sizeof(T_Palette));
           memcpy(temp_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,working_palette,sizeof(T_Palette));
-          Set_nice_menu_colors(color_usage);
+          Set_nice_menu_colors(color_usage,0);
           memcpy(working_palette,Main_palette,sizeof(T_Palette));
           memcpy(Main_palette,temp_palette,sizeof(T_Palette));
           Set_palette(working_palette);
diff --git a/palette.h b/palette.h
index c328b5e3..af687567 100644
--- a/palette.h
+++ b/palette.h
@@ -28,3 +28,9 @@ void Set_palette_RGB_scale(int);
 // The resulting range is [0-255]
 byte Round_palette_component(byte comp);
 
+/*!
+  Adds 4 menu colors in the current palette.
+  @param color_usage An up-to-date color usage table (byte[256]) (read only)
+  @param not_picture 0 if the caller is the palette screen, 1 if it's a preview in the file selector.
+*/
+void Set_nice_menu_colors(dword * color_usage,int not_picture);