How do I overcome XCode object model version error?

Question

I'm currently running OS X 10.7.4 and using XCode 4.3.2. I'm coming back to XCode from not really using it in production since version 2.x. That said, I have a test Core Data application (MacOS not iPhone) I'm getting familiar with. There is 0 code -- all Interface Builder at the moment. I changed the data model a couple days ago, and have been getting the following error since:

The managed object model version used to open the persistent store is incompatible with the one that was used to create the persistent store

I have encountered several related threads, including, but not limited to:

Replace core data model without migration

Incompatible Object Model Version

Wipe all data stored with CoreData when the model has changed

However, none have resolved my problem. Again, I am using no code. Also, despite other pages and forum posts I have encountered:

http://www.matthew-long.com/2007/11/02/the-managed-object-model-version-used-to-open-the-persistent-store-is-incompatible-with-the-one-that-was-used-to-create-the-persistent-store/

…there is no xml file in ~/Library/Application Support/AppName for me to delete. There's actually no folder anywhere in Library with my "AppName". I'm sure the answer is fairly trivial, but I have been beating my head against a wall trying to figure it out.

I'm currently reading the Apple documentation on versioning, etc (http://developer.apple.com/library/mac/#documentation/cocoa/conceptual/CoreDataVersioning/Articles/Introduction.html), but I'm hoping someone will post an answer before my eyes glaze over.

Thanks in advance!