When activating the plugin on a multisite (migration) WordPress, I got the following error
Error creating search views in the database. Deactivate Multisite Global Search and check you have create views privilege in your WordPress database. 'ampo.wp_v_posts' is not VIEW
The tables wp_v_postmeta and wp_v_posts where allready created.
To resolve the problem, I've just deleted the 2 tables, to let the plugin recreate them.