Unable to open iWork documents on my Mac

Question

Been using documents on iCloud for iWork apps (Pages, Numbers, and KeyNote) on my Mac for a few weeks now and it's been working really well but since last week I'm no longer able to open documents from iCloud. It will save or move documents to iCloud but it won't let me open iCloud documents ocne they're there (Error message; "The document “Document_name.numbers” could not be opened."). Although I do edit these documents in the iOS version of the apps, this erro applies to all documents.
Any ideas?
(I'm running Mountain Lion (10.8) and iWork versions v2.2 on a 15-inch mid-2009 MacBook Pro).

Answer 1

Thank you!  This worked for me with one qualification.
I have some very large documents at iCloud and some documents are in folders.  I found it necessary to keep the Data and Documents checkbox in System Preferences unchecked for a several seconds because it takes that long for the document and folders of documents to be removed from my computer.  I also had to wait several seconds before opening the document and folders at iCloud through Pages for the first time after this fix.  The duration of the wait is proportional to the size and the number of the documents. You only have to wait the first time that you open the document or the folder after implementing this fix.  The same thing will happen in Keynote and Numbers.
The above wait is brief and no big deal.  If I listened very closely, I could hear the hard drive in my iMac running to delete the documents after I unchecked the box in System Preferences.  In Pages, there were progess bars that showed the documents being synced. As long as I waited for these things to finish before going to the next step, this solution worked.