TActionParameter=record
    DrIRangeMin,
    DrIRangeMax,
    FDSettings,
    TCMin,
    TCMax:Double;

    OIParamOperation,
    TCToolNo:string;

    class function Empty:TActionParameter; static;
    function IsFilled:Boolean;
  end;

  TPointActionParameters=array of TActionParameter;

.....
{ TActionParameter }

class function TActionParameter.Empty: TActionParameter;
begin
  Result:=default(TActionParameter);
end;

  TCPPoint=class
  private
    FIDCPPoint,
    FIDImage,
    FIDModel:Integer;

    PointActionParameters:TPointActionParameters;

    function GetItemsCount: Integer;
    procedure SetItemsCount(const Value: Integer);
  public
    property ItemsCount:Integer read GetItemsCount write SetItemsCount;
    property Items[Index: Integer]:TActionParameter read GetItem write SetItem;
  end;

function TCPPoint.GetItemsCount: Integer;
begin
  Result:=Length(PointActionParameters);
end;

procedure TCPPoint.SetItemsCount(const Value: Integer);
var
  i:Integer;
begin
  SetLength(PointActionParameters,Value);
  for I := Low(PointActionParameters) to High(PointActionParameters) do
    begin
      PointActionParameters[i]:=PointActionParameters[i].Empty;
    end;
end;

var
  a:TActionParameter;
begin
  a:=CPPoint.Items[AIndex];
  leToolSettingsFact.Text:=FloatToStr(a.FDSettings); //навожу мышью - значение=0, жму F7 -EConvertError '' is not a valid floating value
  leToolID.Text:=IntToStr(a.FDidTool); // аналогично :(