Dear
As suggested you may not assigned the Billing type in VOV8 for your KB.
But remember one thing --are you creating any proforma invoices once after doing Consignment fillup?
As mentioned by you there are No copy controls maintained in VTFL, are you sure?
Normally system will pop up all the Open deliveries into Billing due list based on Copying requirement too in VTFL(Suppose if you maintain Copying routines--in My case --my client assigned 009-proforma--but this bill type has been configured the way F2--invoice type Behaves
-Configuration error)
Hope this helps.
Phanikumar