Yes, I'm also having this problem. I activated this plugin (2.1.8) again to see if the problem had been resolved with any of the fixes applied to 2.5.1 and apparently it hasn't. I've tried to rebuild the tables as per the plugin options, but it didn't help. I'm not sure what else I can try.
Same problem as everyone else is describing. It returns to the login page and doesn't log the user in. MyOpenID account shows a successful login in the history, however. Please help! If this plugin doesn't have support, is there another one out there that somebody could recommend that you've had success with?