Hi simon,
I can not duplicate same problem in my localhost,
Could you enable WP debug mode, repeat actions you mentioned above, and post the debug log here.
http://wp-types.com/documentation/user-guides/debugging-types-and-views/
PHP Debugging
In case you think that Types or Views are doing something wrong (what we call a bug), you should enable PHP error logging. Again, edit your wp-config.php file and add the following:
ini_set('log_errors',TRUE);
ini_set('error_reporting', E_ALL);
ini_set('error_log', dirname(__FILE__) . '/error_log.txt');
This will produce a file called ‘error_log.txt’ in your WordPress root
directory. Make sure that the web server can create and write this file.
If it cannot, use an FTP program to create the file and make it writable to Apache (normally, user www-data).
Regards
Luo