The latest version is not tested on that version. The plugin was first developed on v2.9.x so the basic functionality should work.
The only uncertainty would be the admin page.
Anyway you should be able to install it, check the admin functionality and if it doesn't work remove this plugin (please do tell if it does not work !). The plugin is non-destructive.
Users from a country will be blocked from visiting your site so this is both registering as well as filling in a contact form. You can also choose to block people visiting the admin side of your website.
Hope this helps. If you would like with a little work I will also be able to test it on your specific version.