[adebonis]

Hola.

Ya está solucionado. Este es el código final. La imagen la saco de un ImageList.

Código Delphi [-]
  with Sender as TDBGrid do begin
    if (gdSelected in State) or (gdFocused in State) then begin
      Canvas.Font.Color := clBlack;
      Canvas.Brush.Color := ColorLin;
    end;
    if DataCol = 5 then begin
      if (gdSelected in State) or (gdFocused in State) then begin
        Canvas.Font.Color := clBlack;
        Canvas.Brush.Color := ColorLin;
        end
      else
        Canvas.Brush.Color := clWhite;
      Canvas.FillRect(Rect);
      if Table1.FieldByName('DOC').AsBoolean then begin
        Canvas.FillRect(Rect);
        L := Rect.Left + (Rect.Right - Rect.Left - ImageList1.Width) div 2;
        T := Rect.Top + (Rect.Bottom - Rect.Top - ImageList1.Height) div 2;
        Imagelist1.Draw(Canvas, L, T, 60);
      end;
      end
    else
      DefaultDrawColumnCell(Rect, DataCol, Column, State);
  end;

Gracias román.
Saludos.

Adolfo Bonis Mora
Barcelona