I'm just trying to go through the initial setup for the plugin, and I'm getting a 400 error from Twitter after the oAuth stage. As far as I know, I entered the token etc information in correctly, so I'm not entirely sure what's making things turn out not so well.
I'm not so sure if it's relevant, but debug info shows the callback URL empty. Could that be what's doing it? Running latest version of plugin and WordPress 3.5.