Hi Methen, answering your first question there's a plugin that could be interesting for you: Q2A-User-Manager
I think there's an option to select more than one user and then
- Send email confirmation
Answering your second question, it's very difficult to stop that behaviour, but you'll see some recommendations here. Although it's not your favorite one, email verification seems to be the most effective solution against spammers.
To check your current Q2A version you can take a look at the top of qa-include/qa-base.php, where it defines QA_VERSION
It was previously answered here
I hope it helps you!