old numbers files open with no data; new files can't be created
I just updated a mid-2008 MacBook Pro to OS X 10.7.5. Now, when I open Numbers spreadsheets I get a blank page for all of my spreadsheets. If I try to create a new spreadsheet, again I get a blank page. The Left sidebar shows a new sheet with 2 tables, but the main window is completely blank, and I cannot see any tables, cells, text, etc.
Mac OS X (10.7.2)