Custom Fields Do Not Display on Invoices

-- HikaShop version -- : 2.6.3
-- Joomla version -- : 3.5.1

After upgrading to Hikashop 2.6.3 the custom fields no longer display on the Invoice templates. The values from the custom fields display everywhere else as they should.

The behaviour seems to be isolated to the custom fields created for the product, order and items tables. I tried creating a new custom field for the item table. The new field is not visible anywhere, however, I see that a record was created in the hikaship_field table in the database. I created a new field on the address table and that behaves and display as expected.

I do notice that the options on the custom field listing look different for those custom fields than they do for the custom fields that hit the other tables. Is that expected?

I have attached screenshots of the configuration options on one of the fields, and of the listing of custom fields.

Please let me know if there is any other information you need to help me solve this problem. Thank you for your time!

Thank you Nicolas for your quick reply. I went through steps 1 and 2 with no success. Please advise.

For anyone interested. I did have a chunk of customized code on invoice.php in place to display the shipping and printing methods. After I applied the patches and hot fixes, I deleted the customizations from the invoice.php template, restoring it back to the default. I then added the customized chunk of code back in. That seemed to do the trick. Custom fields are displaying and my customization is back in place.