Create a new email address and use it for this forum. It can be similar to your username if you are doing any sort of business here.
If you mean logging into this forum, by migrating, it's safe to assume your login/password will remain the same?
No. Slickage team can't access to passwords. So they will set up a bot to send emails to every users with a reset link. We can only access the forum if you reset the password. This is what I know. It might change.