Adding a magnet link to MonoTorrent

Question

I have a magnet link and I am trying to create a TorrentManager by using the constructor for magnetlinks, but Visual Studio keeps telling me that it has invalid arguments. What am I doing wrong?

j="magnet:?xt=urn:btih"+myMagnet;
string save = @"C:\Users\Jamie\Downloads";
TorrentSettings torrentSettings = new TorrentSettings(0,10,1000,0);
TorrentManager manager = new TorrentManager(MonoTorrent.InfoHash.FromMagnetLink(j),save,    torrentSettings, save);