diff --git a/factory.c b/factory.c
index d4666157..ee6f9514 100644
--- a/factory.c
+++ b/factory.c
@@ -809,8 +809,9 @@ void Button_Brush_Factory(void)
       }
   		else if (lua_pcall(L, 0, 0, 0) != 0)
       {
-        message = lua_tostring(L, 1);
-        if(message)
+        int stack_size;
+        stack_size= lua_gettop(L);
+        if (stack_size>0 && (message = lua_tostring(L, stack_size))!=NULL)
   			  Verbose_error_message(message);
         else
           Warning_message("Unknown error running script!");
diff --git a/pages.c b/pages.c
index 7ba40e6d..9abe14a9 100644
--- a/pages.c
+++ b/pages.c
@@ -283,7 +283,7 @@ void Redraw_spare_image(void)
        // Copy it in Spare_visible_image
        memcpy(Spare_visible_image.Image,
          Spare_backups->Pages->Image[layer],
-         Spare_image_width*Main_image_height);
+         Spare_image_width*Spare_image_height);
        
        // No depth buffer in the spare
        //memset(Spare_visible_image_depth_buffer.Image,