Multiste Incompatibility Perhaps?
Local stack is Pressmatic with Nginx, MariaDB ad PHP 7.0.3. I'm building a multisite network.
I installed the plugin. It activated fine. After I used it and finished setting up a field how I wanted it to be, I received the following errors: http://drop.rusty.dog/hrUy and http://drop.rusty.dog/hrXW I was also redirected to the blog post list screen.
When revisiting the ACF field group, the same PHP error was present. I disabled and deleted the plugin until it's ironed out.
@leepeterson I'm working on a newer version and will address the issue. The new version is attached to a client project which is not scheduled to be done for a few months, so it'll be a little bit here.
Been a while... assuming this was addressed and the new features merged into master, yeah?