I received an invoice that seemingly cancels a previous invoice from a week earlier. I haven't yet set the bank details, so there couldn't have been a remittance. It includes something like below. What does it mean?

0 PC <sum from previous invoice>

Original delivery quantity: 1  PC
settled by credit memo...:  1- PC
Total net value: 0,00
Some other questions:

Are there any "transfer fees" on remittance?

Can I get the detailed breakdown report along with the invoices rather than after remittance?

Is there a problem with not filling in banking details until the overall sum is substantial enough (beyond the obligatory 100 EUR)?