Cleaning up a Flash 7 code-doesn't work with flashplayer 8

Hi everyone, long time no see,
I have this old code that i can’t use with flash player 8. I know it’s a syntax error, but I can’t figure out which one. I have two errors signaled, here is the code :

1 Pos = Number(Pos)+1;
2 if (Number(Pos)>Number(MsgLen)) {
3 gotoAndPlay(1);
4 }
5 duplicateMovieClip(“LetterTemplate”, “Letter” add Pos, Pos);
6 set(“Letter” add Pos add “/:MyPos”, Pos);
7 set(“Letter” add Pos add “/Letter/:Char”, substring(Message, Pos, 1));
8 setProperty(“Letter” add Pos, _visible, Trus);

The error is on line 5, apparently i’m missing a ‘,’ or a ‘)’.

AND i have another error :

removeMovieClip("…/Letter" add MyPos);

and I’m still missing a ‘,’ or a ‘)’.

Can anyone help? I’m not used yet to the new syntax…
And I bet it’s pretty simple!!!

Thanks in advance…