I am working with WordPress(3.6-RC1-24717), and it seems that when trying to create a post/custom post type it throws the following error:
Fatal error: Call to undefined function wp_verify_nonce() in ../wp-content/plugins/advanced-custom-fields/core/controllers/everything_fields.php on line 402
Tracing that through it seems to be thrown at wp-includes/taxonomy.php running the ‘create_term’ action on ln.2135. I have removed all of my ACF fields from the install and it’s still happening.
There is some mention of this on old WordPress support posts about hooking into into actions before everything has been loaded in. So perhaps they’ve changed the order of things in 3.6?
I am afraid I am suitable inexperienced with this level of plugin development to do much more than point out the bug. But happy to help out on this issue.
Thanks for getting back to me so quickly about this, just to update my findings. I tracked the issue down to the issue to a conflict between another plugins. Apologies it didn’t occur to me to check that first! Just to excited about using the new forums!