In addition to setting permissions appropriately, a good backup plan with transaction logs is key to recovery from user error, malicious action or hardware failure. The QdabraDBXL and QdabraUtilities (QdabraSamples in v2.3) should be backed up regularly, and depending on the frequency of updates, transaction log backups at frequent intervals (e.g. 15 minutes). That way your data loss is limited to the interval of your transaction log backups.
The sql tables you are shredding to are recoverable by restoring the xml form content from backups and then reshredding your document type.
You can also implement auditting on tables where you need to provide further activity tracking.