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 WM_LBUTTONDOWN: begin
      case FWMHitResult of
        HTCAPTION: begin
         // ReleaseCapture(TForm(FSkinedForm).Handle);
          TForm(FSkinedForm).Perform(WM_SYSCOMMAND,SC_MOVE or 1,0);
        end;
      end;

    end;                    

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WM_LBUTTONDOWN:
      begin
        MoveWindowWithMouse(Dlg, lParam);
      end;                    

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procedure MoveWindowWithMouse(Handle: THandle; lParam: LPARAM);
begin
  SetCursor(LoadCursor(0, IDC_SIZEALL));
  SendMessage(Handle, WM_NCLBUTTONDOWN, HTCAPTION, lParam);
end;