如何创建一个NetMeeting的PreviewOnly窗口在窗体上(100分)

const
s = 'MODE=PreviewOnly';
netmeeting = '3E9BAF2D-7A79-11d2-9334-0000F875AE17';
var
wnd: THandle;
nmis: NmInitStruct;
i: integer;
str: PWideChar;
clsid: TGUID;
a: POleStr;
begin
fillchar(nmis.str,260,#0);
for i := 0 to length('MODE=PreviewOnly')-1 do
begin
nmis.str := ord(s[i+1]);
end;
clsid.D1 := $3E9BAF2D;
clsid.D2 := $7A79;
clsid.d3 := $11d2;
clsid.D4[0] := $93;
clsid.D4[1] := $34;
clsid.D4[2] := $00;
clsid.D4[3] := $00;
clsid.D4[4] := $F8;
clsid.D4[5] := $75;
clsid.D4[6] := $AE;
clsid.D4[7] := $17;

StringFromCLSID(clsid,a);
nmis.wSize := sizeof(nmis.str);
wnd := Createwindow('Application',pchar(a),
0,
10,10,0,0,handle,
0,
hinstance,
@nmis);
if wnd <> 0 then
showmessage('ok');
//wnd怎么都是o

NmInitStruct = record
wSize: WORD;
str: array [0..259] of byte;
end;

没有人会吗？帮帮我啊