This problem appears selective, and attempts to reproduce have been 
unsuccessful.  I have therefor attached my golf spreadsheet which displays the 
problem.

On opening the spread sheet, in the "Full Summary" sheet, at G20:I20, all cells 
are blank.  If you change C1 to 11.2003, then back to 12.2003, G20:I20 now has 
the correct data in it.  An individual cell can be fixed by changing the 
formula for that cell and removing the modification then pressing enter (eg. 
edit formula, remove last closing bracket then put it back, and press enter)

The cell is empty (I believe) because ISERROR is getting an error somehow from 
the DGET done in this cell.  To prove this theory, I moved the DGET out of the 
formula into a cell to the side, and had the G20:I20 range just refer to the 
newly created field.  The problem still occurs.

The blank field problem is predominantly on load.  Using the spread sheet while 
it's open seems fine, but if you save, then reload, the information is gone. 
until to force the cells to recalculate (either by changing C1 as above, or by 
modifying the formula, removing the modification then pressing enter - I guess 
that this forces the cell to recalculate?) 

It appears that only this small range displays this problem.  I removed several 
individuals form the sheet to try to reduce the work that the sheet has to do, 
but this did not fix the problem.

Sorry that I couldn't narrow down the problem further... I hope that there's 
enough information here... I tried to load this file under Linux Open Office 
1.1, and Windows Open Office 1.1, and both displayed the problem, so I'm 
presuming that it's very reproducable.