When enabling with http://searchwp.com I get this fatal error:
PHP Fatal error: Call to a member function get() on a non-object in /wp-content/plugins/ssh-sftp-updater-support/class-wp-filesystem-ssh2.php on line 124
This is the only plugin it happens with, but oddly enough this is also the only plugin I've ever had conflict with SearchWP either. So, since the error is being thrown in your plugin, I thought I'd give you a shout in the event you could point in the right direction on why this could be happening. Thanks!