After upgrade from 2.5.9.4 to 3.5.6.6, gift certificate orders through VirtueMart not creating coupons.

We upgraded from 2.5.9.4 to 3.5.6.6 in late October and since then gift certificate orders aren't even creating the coupons, let alone sending out emails.  I can confirm that there's no entry in #__awocoupon_voucher_customer_code with a test order buying a gift certificate.
I checked the gift certificate images folder, and it's at /administrator/components/com_awocoupon/awocoupon/media/giftcert/images as expected.  Any ideas?

Never mind.  I solved this.  We previously had our own image in the giftcert/images directory and it didn't make it to the new location.  I restored it from a backup and now the gift certificates are getting created and the emails are getting sent.