Gmail setup for tweetlater autoreply forward problem

I am having trouble setting up auto reply for a new follow in gmail. I get the email from twitter saying someone has followed me and my filter seems to find those emails if i do a 'test searc', yet gmail doesn't seem to forward the email on to tweetlater. In the 'create filter' area of gmail, can I only have 'forward' checkbox ticked? I do have 'mark as read' and 'apply as label' checked also but didn't think that would be an issue - ie i would have thought gmail does all items checked.