For switching from auto to manual renewel of subscriptions you will need to do the following:
Go to https://secure.2co.com/myaccount/ Enter the email address that you used to purchase FBX to create a 2checkout account. Once you are logged into that account, you need to go to "My Products". There you should see your subscription and be able to enable / disable auto-renewal.For the other issue, we'll need to take a look at your log files to check what is going on so please use the Report a Problem option on FBX's Support tab to send those to us.