Can I use TstringList in script? with FastReport pro 6.8 ,RadStudio 10.4.2

Hi,I am watanabe nobuo.

I use FastReport pro 6.8 with RadStudil 10.4.2.

AccessViolation occured one of two showreport;

Button1 have onClick Event;

like,

procedure Tform1.button1Click(Sender:tObject);

begin

 FastReport.showReport();

end;

1st button1click go well;

2nd button1click occures accessViolation;

3rd button1click go well;

4th button1click occures accessViolation;

5rd button1click go well;

6th button1click occures accessViolation;

.......

In FastReport Script,i use variable typed TStringList;

And I Create it,and Free it.

Maybe the accessviolation is occured when I use it.

Not When I create it or Free it.

When I use array of string,instead of TStringlis,

No error is occured.

Can't I use TStringList in FastReport Script?

Sincerely.

<sample code>

var

 slName:tStringList;

procedure GroupHeader1OnBeforePrint(Sender: TfrxComponent);

var

 i:integer;                                              

begin

 for i:=slName.count -1 downto 0 do// Maybe error is occured here

 begin

   if slName[i]=inttostr(<frDBu."name">)

   then begin

     dispData := slPages[i];   

     exit;                 

   end;             

 end;           

end;

procedure frxReport1OnStartReport(Sender: TfrxComponent);

begin

 if engine.FinalPass then exit;

 slName := tStringList.create;

end;

procedure frxReport1OnStopReport(Sender: TfrxComponent);

begin

 slName.Free;         

end;

begin

end.