This plugin has been a nightmare. It looks easy install and use on the outside, but it's not. It's single biggest problem after looking at the php code was that it doesn't account for the url scripting changes that Google made when it took over Feedburner (which has been a while now). Example= 'uri' instead of 'ffid' and so on. So what happens? It installs and looks pretty on your site, but when someone goes to subscribe, they get this message, "The feed does not have subscriptions by email enabled" even though it has been enabled. And the forums at VivoCiti have a bunch of people asking the same question with no answers. I'm really disappointed.
Owner's replyhi pal, apologize for the late support due to other commitment. i have released new version to support google new format.
you can download it now
rgds,
anen wu