The projectile cover creation menu can be used to create a new projectile cover. In this menu, you need to choose what type of projectile cover you would like to add. This menu should look like this:

There should be a 'Cancel' button and a button for each type of projectile cover, which are currently only 'Sphere' and 'Custom'. The 'Cancel' button will take you back to the projectile cover overview, without adding a new projectile cover. The other buttons will take you to the edit menu for the corresponding projectile cover type. I will describe them briefly: