unit ButtonPanel;
...
type

 TButtonPanel = class;
 TShifts = class(TPersistent) // класс для хранения группы свойств
 private
   FCaptionDX: integer;
   FCaptionDY: integer;
   FAOwner : TButtonPanel;
   procedure SetCaptionDX(const Value: integer);
   procedure SetCaptionDY(const Value: integer);
 public
   constructor Create(AOwner: TButtonPanel);
   destructor Destroy; override;
   procedure Assign(Source: TPersistent); override;
 published
   property CaptionDX : integer read FCaptionDX write SetCaptionDX;
   property CaptionDY : integer read FCaptionDY write SetCaptionDY;
 end;

 TButtonPanel = class(TPanel)
   ...
 public
   constructor Create(AOwner: TComponent); override;
   destructor Destroy; override;
 protected
   procedure Paint; override; // там будем отрисовывать панельку с учётом смещений
 published
   property Shifts : TShifts read FShifts;
 end;

procedure Register;

implementation
...

procedure Register;
begin
 RegisterComponents('Ed', [TButtonPanel]);
end;

constructor TButtonPanel.Create(AOwner: TComponent);
begin
 inherited;
 FShifts := TShifts.Create(self);
   ...
end;

destructor TButtonPanel.Destroy;
begin
   ...
 FShifts.Free;
 inherited;
end;

 ...

procedure TShifts.Assign(Source: TPersistent);
begin
 inherited Assign(Source);
 if Source is TShifts then
 begin
   FCaptionDX := TShifts(Source).CaptionDX;
   FCaptionDY := TShifts(Source).CaptionDY;
 end;
end;

constructor TShifts.Create(AOwner: TButtonPanel);
begin
 FAOwner := AOwner;
 FCaptionDX := 0;
 FCaptionDY := 0;
end;

destructor TShifts.Destroy;
begin
 inherited;
end;

procedure TShifts.SetCaptionDX(const Value: integer);
begin
 FCaptionDX := Value;
 FAOwner.Invalidate;
end;

procedure TShifts.SetCaptionDY(const Value: integer);
begin
 FCaptionDY := Value;
 FAOwner.Invalidate;
end;

end.

   property CaptionDX : integer read FCaptionDX write SetCaptionDX stored true;
   property CaptionDY : integer read FCaptionDY write SetCaptionDY stored true;

   property CaptionDX : integer read FCaptionDX write SetCaptionDX nodefault;
   property CaptionDY : integer read FCaptionDY write SetCaptionDY nodefault;

property Shifts : TShifts read FShifts write SetShifts;

procedure SetShifts;
begin
 FShifts.Assign(Value);
end;