If that sale still hasn't shown up, try the following:
1. On the dashboard, click "Account Info"
2. In the "Sold Duration Days" field, enter 3 days (or however far back your missing sale is plus one day)
3. Click "Reset Download Duration" (It's the button directly below the field
4. Navigate to the Sold Item List
5. Click "Download Sales from eBay"
If any sales entries are received from eBay that aren't currently in the list, they should be added. Let me know if this helps. I'll check back as much as I can during the holiday to make sure you get your data. I feel pretty confident that things are good moving forward though.