Possible to deny membership?

Hello all,

First of all thanks for the great, simple membership tool! Exactly what I was looking for.

After installation of the plugin, the register form showed “Heads up! Currently the registration is not allowed” (or something similar). So I went to the settings (General) and activated the option that “everyone is allowed to register” or similar, as I use it in German. Now it seems to be activated, but I wonder if it is possible to control a new registration before accepting it; or otherwise said: if someone wants to register, do I have to opportunity to first check who wants to register and possibly deny the membership?

PS: I use the version 1.0.11 of your plugin, WP 4.9.1, and other Plugins installed are AntispamBee, BackWPup, Contact Form 7, Facebook Auto Publish and Email Subscribers & Newsletters.

Thank you for your help,
Michael