Delphi-PRAXiS - Delphi Anwendung unicodefähig machen?

Ich möchte folgenden Code bzw. Anwendung unicodefähig machen, aber irgendwie klappt es nicht. Das mit den PChar und PAnsiChar verstehe ich nicht so ganz... :gruebel:
Kann mir da jemand ein Paar Tipps geben? Danke!
Delphi-Quellcode:
			  public

    { Public declarations }

    procedure WndProc(var Msg: TMessage); override;

  end;

var

  Form1: TForm1;

  Proxy: array [0..99] of AnsiChar; //proxy server

  cthread: DWORD = 0;

  chan: HSTREAM = 0;

  win: hwnd;

implementation

const

  urls: array[0..9] of AnsiString = ( // preset stream URLs

   'http://174.36.213.41:8000/stream','http://www.radioparadise.com/musiclinks/rp_32.m3u',

   'http://ogg2.as34763.net/vr160.ogg', 'http://ogg2.as34763.net/vr32.ogg',

   'http://ogg2.as34763.net/a8160.ogg', 'http://ogg2.as34763.net/a832.ogg',

   'http://somafm.com/secretagent.pls', 'http://somafm.com/secretagent24.pls',

   'http://somafm.com/suburbsofgoa.pls', 'http://somafm.com/suburbsofgoa24.pls'

    );

{$R *.dfm}

  { display error messages }

procedure Error(es: string);

begin

  MessageBox(win, PChar(es + #13#10 + '(error code: ' + IntToStr(BASS_ErrorGetCode) +

    ')'), nil, 0);

end;

{ update stream title from metadata }

procedure DoMeta();

var

  meta: PAnsiChar;

  p: Integer;

begin

  meta := BASS_ChannelGetTags(chan, BASS_TAG_META);

  if (meta <> nil) then

  begin

    p := Pos('StreamTitle=', String(AnsiString(meta)));

    if (p = 0) then

      Exit;

    p := p + 13;

    SendMessage(win, WM_INFO_UPDATE, 7, DWORD(PAnsiChar(AnsiString(Copy(meta, p, Pos(';', String(meta)) - p - 1)))));

  end;

end;

procedure MetaSync(handle: HSYNC; channel, data: DWORD; user: Pointer); stdcall;

begin

  DoMeta();

end;

procedure StatusProc(buffer: Pointer; len: DWORD; user: Pointer); stdcall;

begin

  if (buffer <> nil) and (len = 0) then

    SendMessage(win, WM_INFO_UPDATE, 8, DWORD(PAnsiChar(buffer)));

end;

function OpenURL(url: PAnsiChar): Integer;

var

  icy: PAnsiChar;

  Len, Progress: DWORD;

begin

  Result := 0;

  BASS_StreamFree(chan); // close old stream

  progress := 0;

  SendMessage(win, WM_INFO_UPDATE, 0, 0); // reset the Labels and trying connecting

  chan := BASS_StreamCreateURL(url, 0, BASS_STREAM_BLOCK or BASS_STREAM_STATUS or BASS_STREAM_AUTOFREE, @StatusProc, nil);

  if (chan = 0) then

  begin

    //lets catch the error here inside the Thread

    // and send it to the WndProc

    SendMessage(win, WM_INFO_UPDATE, 1, Bass_ErrorGetCode()); // Oops Error

  end

  else

  begin

    // Progress

    repeat

      len := BASS_StreamGetFilePosition(chan, BASS_FILEPOS_END);

      if (len = DW_Error) then

        break; // something's gone wrong! (eg. BASS_Free called)

      progress := BASS_StreamGetFilePosition(chan, BASS_FILEPOS_BUFFER) * 100 div len;

      // percentage of buffer filled

      SendMessage(win, WM_INFO_UPDATE, 2, progress); // show the Progess value in the label

    until

      (progress > 75) or (BASS_StreamGetFilePosition(chan, BASS_FILEPOS_CONNECTED) = 0); // over 75% full (or end of download)

    // get the broadcast name and bitrate

    icy := BASS_ChannelGetTags(chan, BASS_TAG_ICY);

    if (icy = nil) then

      icy := BASS_ChannelGetTags(chan, BASS_TAG_HTTP); // no ICY tags, try HTTP

    if (icy <> nil) then

      while (icy^ <> #0) do

      begin

        if (Copy(icy, 1, 9) = 'icy-name:') then

          SendMessage(win, WM_INFO_UPDATE, 3, DWORD(PAnsiChar(Copy(icy, 10, MaxInt))))

        else if (Copy(icy, 1, 7) = 'icy-br:') then

          SendMessage(win, WM_INFO_UPDATE, 4, DWORD(PAnsiChar('bitrate: ' + Copy(icy, 8, MaxInt))));

        icy := icy + Length(icy) + 1;

      end;

    // get the stream title and set sync for subsequent titles

    DoMeta();

    BASS_ChannelSetSync(chan, BASS_SYNC_META, 0, @MetaSync, nil);

    // play it!

    BASS_ChannelPlay(chan, FALSE);

  end;

  cthread := 0;

end;

procedure TForm1.WndProc(var Msg: TMessage);

// to be threadsave we are passing all Canvas Stuff(e.g. Labels) to this messages

begin

  inherited;

  if Msg.Msg = WM_INFO_UPDATE then

    case msg.WParam of

      0:

        begin

          Label4.Caption := 'connecting...';

          Label3.Caption := '';

          Label5.Caption := '';

        end;

      1:

        begin

          Label4.Caption := 'not playing';

          //Error('Can''t play the stream');

         MessageBox(win, PChar('Can''t play the stream' + #13#10 + '(error code: ' +

            IntToStr(msg.LParam)+')'), nil, 0);

        end;

      2: Label4.Caption := Format('buffering... %d%%', [msg.LParam]);

      3: Label4.Caption := String(PAnsiChar(msg.LParam));

      4: Label5.Caption := String(PAnsiChar(msg.LParam));

      5: Label5.Caption := String(PAnsiChar(msg.LParam));

      6: Label3.Caption := String(PAnsiChar(msg.LParam));

      7: Label3.Caption := String(PAnsiChar(msg.LParam));

      8: Label5.Caption := String(PAnsiChar(msg.LParam));

    end;

end;                       

procedure TForm1.FormCreate(Sender: TObject);

begin

  // check the correct BASS was loaded

  win := handle;

  if (HIWORD(BASS_GetVersion) <> BASSVERSION) then

  begin

    MessageBox(0, 'An incorrect version of BASS.DLL was loaded', nil, MB_ICONERROR);

    Halt;

  end;

  if (not BASS_Init(-1, 44100, 0, Handle, nil)) then

  begin

    Error('Can''t initialize device');

    Halt;

  end;

  BASS_SetConfig(BASS_CONFIG_NET_PLAYLIST, 1); // enable playlist processing

  BASS_SetConfig(BASS_CONFIG_NET_PREBUF, 0); // minimize automatic pre-buffering, so we can do it (and display it) instead

  BASS_SetConfigPtr(BASS_CONFIG_NET_PROXY, @proxy[0]); // setup proxy server location

end;

procedure TForm1.FormDestroy(Sender: TObject);

begin

  BASS_Free;

end;

procedure TForm1.Button1Click(Sender: TObject);

var

  ThreadId: Cardinal;

begin

  StrPCopy(proxy,ed_ProxyServer.Text); // copy the Servertext to the Proxy array

  if (cthread <> 0) then

    MessageBeep(0)

  else

    cthread := BeginThread(nil, 0, @OpenURL, PAnsiChar(urls[TButton(Sender).Tag]), 0, ThreadId);

end;

procedure TForm1.cbDirectConnectionClick(Sender: TObject);

begin

  if not TCheckbox(Sender).Checked then

    BASS_SetConfigPtr(BASS_CONFIG_NET_PROXY, @proxy[0]) // enable proxy

  else

    BASS_SetConfigPtr(BASS_CONFIG_NET_PROXY, nil); // disable proxy

end;

end.