Membership Documentation

Hi - I'm looking for some real documentation for the Membership plugin so I can suit it to my needs without waiting on support for each and every question. Some things I need off the bat are examples of authentication checks within PHP for custom utilization (say, integrating with other plugins), how to create a custom login screen (was told this is possible out of the box), and how to customize the registration screens (the markup, not just CSS). There are plenty of things I need to do, but some documentation would get me running and leave only a few questions to throw at you here, sounds like your team's busy!