Is this plugin still supported?

That’s true. We are discussing the idea of integrating this feature to Antispam Bee (https://de.www.ads-software.com/plugins/antispam-bee). That’s why it is so quiet here …

If you are looking for alternatives, there are some plugins using the underlying tool:
https://github.com/splorp/wordpress-comment-blacklist#automatic-updates-via-plugin

Or you will be patient and see what is coming in the future. ??

All the best,
Torsten

I have been using this plugin under recent versions of WordPress, up to and including the current 4.7.1 release. I can report that it functions as promised and really doesn’t require any updating at this time.

By the way, I’m the creator of the Comment Blacklist for WordPress as mentioned.