I've just upgraded to business license for a clients site and installed the CM add-on and I get the following:
Fatal error: Cannot redeclare class CS_REST_NativeJsonSerialiser in /home/guild/public_html/wp-content/plugins/gravityformscampaignmonitor/api/class/serialisation.php on line 81
All the forms on the site break when this add-on is activated.
Clients website uses WordPress 3.0.1.
Can someone please help me, I have no idea how to fix this.