Open is being blocked and hangin as it waits to open the file (not likely)
You're right -- this seems highly unlikely in light of the fact that the script continues and processes the next record in sequence just fine.
Something is erasing the file after it is written.
Maybe. It's the next angle to pursue I suppose. *grumble* I pretty well exhausted this one when I first learned of the problem... "Is the reaper functioning properly? etc."
Something is intercepting your die messages.
I tested the test die call and it died cleanly.