[roman]

Vamos a ver:

Ayer hice algo así:

unit Element;

interface

uses
  Windows, Classes;

type
  TPoints = array of TPoint;
  TElement = class(TComponent)
  private
    FPoints: TPoints;
    procedure SetPoints(const Value: TPoints);

    procedure ReadPoints(Reader: TReader);
    procedure WritePoints(Writer: TWriter);

  protected
    procedure DefineProperties(Filer: TFiler); override;

  public
    property Points: TPoints read FPoints write SetPoints;
  end;

procedure Register;

implementation

{ TElement }

procedure TElement.DefineProperties(Filer: TFiler);
begin
  inherited;

  Filer.DefineProperty('Points', ReadPoints, WritePoints, Length(FPoints) > 0);
end;

procedure TElement.ReadPoints(Reader: TReader);
var
  I: Integer;

begin
  Reader.ReadListBegin;
  I := 0;
  while not Reader.EndOfList do
  begin
    SetLength(FPoints, I + 1);
    FPoints[i].X := Reader.ReadInteger;
    FPoints[i].Y := Reader.ReadInteger;
    Inc(I);
  end;
  Reader.ReadListEnd;
end;

procedure TElement.SetPoints(const Value: TPoints);
begin
  FPoints := Copy(Value);
end;

procedure TElement.WritePoints(Writer: TWriter);
var
  I: Integer;

begin
  for I := 0 to Length(FPoints) - 1 do
  begin
    Writer.WriteInteger(FPoints[i].X);
    Writer.WriteInteger(FPoints[i].Y);
  end;
end;

procedure Register;
begin
  RegisterComponents('Samples', [TElement]);
end;

end.

Entonce no estaba tan errado. Claro que es mejor usar como tú un contador de los puntos.

// Saludos