There is no such functionality in the app but you can use IgnoreList for excluding folders/files from sync. Please see this guide http://forum.bittorrent.com/topic/17782-bittorrent-sync-faq-unofficial/ Thanks!
Hi! In some cases BTSync may re-sync files after moving them to another directory in the current versions. Devs are working on it and it will be fixed in the next releases. Thanks for reporting!