I much prefer this plugin to "service" plugin alternatives that would send my site visitors' information through third party sites. Functionality is everything I need and then some. When I began to experience a problem with Facebook logins, Miled resolved the issue in short order.
I think the key to success when requesting help from a plugin author is to do your homework first. In other words, try what you can think to do, document what you tried, and communicate that to the author. You'll find that tends to beat griping and ranting. There are a number of diagnostic tools built into this plugin to help the author help you. Use them.