[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName=My Program

[Files]
; this will make the bitmap you want to show part of the setup
; but only for time when the installer runs; it won't be copied
; elsewhere than to the installer's temporary folder
Source: "C:\Users\MostDeviantAsiedu\Desktop\setup\Logo.bmp"; DestDir: "{tmp}"; Flags: dontcopy

[Code]
var
  WelcomePageID: Integer;
  BitmapImage: TBitmapImage;

procedure InitializeWizard;
var
  WelcomePage: TWizardPage;
begin
  WelcomePage := CreateCustomPage(wpWelcome, '', '');
  WelcomePageID := WelcomePage.ID;
  BitmapImage := TBitmapImage.Create(WizardForm);
  // this will extract the included Logo.bmp file from the [Files] section
  // to the Inno Setup temporary folder
  ExtractTemporaryFile('Logo.bmp');
  // the ExpandConstant('{tmp}\Logo.bmp') line will expand path to that
  // temporary file extracted before
  BitmapImage.Bitmap.LoadFromFile(ExpandConstant('{tmp}\Logo.bmp'));
  BitmapImage.Top := 0;
  BitmapImage.Left := 0;
  BitmapImage.AutoSize := True;
  BitmapImage.Cursor := crHand;
  BitmapImage.Visible := False;
  BitmapImage.Parent := WizardForm.InnerPage;
end;

procedure CurPageChanged(CurPageID: Integer);
begin
  BitmapImage.Visible := CurPageID = WelcomePageID;
  WizardForm.Bevel1.Visible := CurPageID <> WelcomePageID;
  WizardForm.MainPanel.Visible := CurPageID <> WelcomePageID;
  WizardForm.InnerNotebook.Visible := CurPageID <> WelcomePageID;
end;