The "free nights" appear to have been loaded properly today. ^ Thanks to everyone who contributed to fixing this (and to getting it taken seriously in the first place).
I haven't received any instructions on how to redeem, so will have to wait and see what happens when I try to book a suitable stay. The expiry date hasn't been changed, so we have a little less than a year rather than a little more.
EDITED TO ADD: If I try to reserve a Westin using points the following message appears: "You have eligible e-certificates that match your reservation".
The nice thing is it looks like you got 4 free nights instead of one 4 night coupon. ^