BP Group Email goes to blank page on "send email"

BP Group Email is going to a blank page when the "send email" tab is selected. I'm not sure what's going on. The URL referred to by the "send email" tab is of the form http://www.partiallyexaminedlife.com/groups/citizengroup/email, the output for which ends up being completely empty of HTML.

Any thoughts?

I'm using WP 4.0 with BP Group Email 1.0.6.

Dylan Casey