Lazarus BitMap.LoadFromFile

Hello,

1°
Translating a program from Delphi7, i got an error with a 
tBitmap.LoadFromFile

System give me back fellowing error:
Project raise exception 'External SIGSEGV'

Here is my Lazarus defective code:

program project1;
{$mode objfpc}{$H+}
uses
   {$IFDEF UNIX}{$IFDEF UseCThreads}
   cthreads,
   {$ENDIF}{$ENDIF}
   Classes
   { add your units here }
   , SysUtils
   , Graphics
   ;
var bm: tBitMap;
     FileName: String;
begin
   bm := TBitMap.Create;
   FileName := 'c:\temp\test.bmp';
   if FileExists(FileName) then
     begin
       WriteLn('Before LoadFromFile'); ReadLn;
       bm.LoadFromFile(FileName);
       WriteLn('After LoadFromFile'); ReadLn;
     end
   else
     WriteLn('File not found'); ReadLn;
end.

In Console output I get 'Before LoadFromFile' but never 'After
LoadFromFile'


2°
I precise that I don t want to have a graphical output of BitMap, but 
just read pixel data, so after how can I access to pixels

In Delphi I use Ptr to access to pixel with:

var Ptr: Pointer;
function GetImagePointer(ABitmap: TBitMap): Pointer;
var
   Info: Windows.TBitMap;
begin // converts bitmaps to pointers ect.
   Result := nil;
   if Assigned(ABitmap) then
     begin
       GetObject(ABitmap.Handle, SizeOf(Info), @[EMAIL PROTECTED]
);
       Result := Info.bmBits;
     end;
end;
Ptr := GetImagePointer(Bitmap);

Thanks in advance for any help