It sure is, to start it automatically all you'd have to do is add the following code to your script, right after the OnGetScriptMenu() function:
code:
function OnEvent_Signin(Email) {
qfile = fso.OpenTextFile(MsgPlus.ScriptFilesPath + "\\quotes.txt", 1);
MsgPlus.AddTimer("sendmsg", timer * 1000);
Messenger.MyPersonalMessage = qfile.ReadLine();
}
That is the same code used when you push the "Start" menu button, except it executes when you sign in to msn.
Edit: As for the loop, I am unsure how that would be done (sorry, new to this). Also, tested it and it works.