AdvStringGrid cell can not move by down cursor key

AdvStringGrid cell can not move by down cursor key.

AdvStringGrid put on the Form1,
and the FormCreate event is below.

procedure TForm1.FormCreate(Sender: TObject);
begin
    AdvStringGrid1.ColCount := 2;
    AdvStringGrid1.RowCount := 6;
    AdvStringGrid1.MergeCells(1,1,1,2);
    AdvStringGrid1.MergeCells(1,3,1,2);
end;

It can not move from 4 to 5 row of cell selection.
even if a down Cursor key is pressed,

I use AdvStringGrid ver 8.3.5.2 and Delphi XE8 Japanese edition.

We traced & solved this issue. The next update will address this.