Hi,
The "click layout assist" button was replaced with the improved and simplified "Hide 'h' Columns" button which toggles all of the columns with an 'h' label between hidden and unhidden.
Here is an overview video linked to the timestamp where that is discussed:
https://youtu.be/52av5AyjUmg?t=300If you download a sale before the refund is issued, you can add the refund information by resetting the download duration.
On the account info / settings tab, change the number of days to go back far enough for that sale (up to 90 days), click the 'reset duration' button, and then redownload your sales.
Let me know if you still have any trouble.