核心数据：重新打开文档时出现奇怪的绑定错误。救命？

I have been building a core data application to administrate some data and I've been stumped by a bug that indicates my objects aren't KVO compliant. However, I haven't modified the default KVO compliance of the NSManagedObject, and now I'm left scratching my head.I have been building a core data application to