How to change permissions on an Agenda block?

Question

So, I'm working with a drupal 7 site using Login Toboggan and I'm running into an issue. The title of my calendar block shows up for anonymous users on a page they shouldn't be able to access. So, the block title is displayed on the user-login screen and when I disable the Login Toboggan module the calendar block shows up on the 403 screen, because the block doesn't have any role restrictions. The issue is that the calendar block is generated from the code in the Agenda module (I think) and it sets the Body field as required. If I change the body field, I break the calendar application, since the body field is required I can't update the role permissions. So, I either need to change the settings on the body field, or change the role permissions in the Agenda module's code. Not sure what the best way to approach this is.