Issue with custom field (type file) in OC 3.0.2.0

Hi, I am using OC 3.0.2.0 and set up a custom field which appears in the checkout process. The field type is FILE and it purpose is to allow customers to upload and attach a file when they are placing their order. This is then supposed to appear as an attachment in the order confirmation email so that the file can be saved in our email client software, and also in the back end order details.

There are two issues:
(1) The file attached by the customer during checkout does not get attached to the order confirmation email that gets sent to admin. We've tried various different email addresses as the admin email, and none of them receive the attachment. Other details come through fine.
(2) In the back end, if I go to Sales -> Orders, click the "eye" button to view the order, then go down to Order History and click the Additional tab, I CAN see the name of the file under Account Custom Fields. But I can't download it - it just shows the NAME of the file with no download link.

How do I fix these two issues please?

Thanks!

Has no one else come across this issue?

Can someone please help with this???