Open Radar

 
Steps to Reproduce:
1. I ran the new Numbers for iOS 7 for the first time. Dismissed the intro guide.
2. Opened my most important document. It said it wouldn't be openable in old Numbers again if I opened it. Fine, I tapped Yes.
3. Made some modifications to the document, keeping it open on the table beside me with screen unlocked for a few minutes.
4. Opened the new Numbers for Mac, dismissed the intro guide.
5. When I clicked "Open Spreadsheet", my three existing documents were shown in the open dialog.
6. After about a second, my most important document disappeared from the list.
7. At the exact same time, the document closed on my iPhone, and disappeared from the document list. One of the devices (don't remember which) said the document was "deleted in another location".

Trust me, I did **NOT** delete the document in either location. I was not touching either device when the document disappeared.

I'm not using iCloud again. This is atrociously bad. If I didn't know my way around ~/Library or my Time Machine had been broken, that document would've been lost forever. An *iCloud document* would've been lost forever!

Expected Results:
Not losing my data.

Actual Results:
Lost my data.