Redirect using Ultimate Facebook

Error received after activating a new user account:

Fatal error: Cannot use object of type WP_Error as array in /home/acadmin/public_html/wp-content/plugins/wpmu_dev_maps_plugin/lib/class_agm_map_model.php on line 561

Once I refresh the page I'm prompted for an activation key. I do receive the new user email and am able to log in using the provided credentials. Needing to know if I need to disable this plugin and locate another one.
Any assistance appreciated.