Register Plus Redux Not Registering Users

I am not able to register any of my users as of WP 3.1.3 change. I am using Register Plus Redux 3.7.3. I tried registering a user and after I submit, it comes back with a 404 error. The user also did not get created in the database.

Don’t know if this is it, but I have installed WordPress in another directory (lets call it the wp directory). In the settings screen, it says that by leaving the redirect link empty users will be redirected to (notice no wp directory because you are using home_url):

http://www.mysite.com/wp-login.php?checkemail=registered

Subsequently, after the user registers, nothing is stored in the database and the user is taken to a 404 page:

So I put in the redirect the link above and it still isn’t redirecting to this page. The link works (with the wp) if I browse directly to it, but users are not being taken there.

I’ve disabled the plugin and tested – the default registration works fine.