Yes to both questions. Here's excerpt from aMember:
"Integration plugins
aMember Pro has ability to integrate with third-party applications. If you have such an integration plugin installed and configured, aMember will maintain users database (table) in third-party script, so your aMember subscribers can be automatically added to your Bulletin Board, CMS or HelpDesk users database. When their subscription expires, users will be automatically disabled or (rarely) removed from third-party database.
Please note - this integration is one-way: users are copied from from aMember to third-party script, and never vice-versa (from third-party script to aMember). Second way would require changes to your third-party script, that would be hard to maintain and would make troubles to upgrade your third-party script.
Also, if user has the same username and password in aMember and a third-party script, it is often possible to implement single-login - when user is logged-in into aMember, it becomes logged-in into third-party script and vice-versa. "
Dave