To send UBL invoices from FID-Managerr you add the UBL line [[INVOICES_UBL]] to the email template you use for sending invoices. This adds a link with the UBL invoice to your email. You can do this in the template 'FAC - Send invoices via email' in the submenu 'Templates' under the 'Communication' menu. Next, send the email with link to the adrdess your customer is using to receive Billit documents in Fast input. Billit will collect the UBL invoice from the link as soon as the email arrives.
Your email with UBL link will now appear in Fast input. Billit detects the UBL link automatically. By default, imported documents must be checked here but you can also put UBL documents in the expenses list automatically. To enable this, go to 'Settings', the 'Bèta' segment and tick the box next to 'Fast input: process UBL automatically'.