Lockbox transmission invalid application due to currency difference

1. Bank Statement in Cash Management has a statement line in PLN currency which is reconciled to an AR invoice with EUR currency. This is because in Poland, sometimes the VAT is paid separately by the customer in the local currency, even if the invoice itself is in EUR.
2. When running CLE: Selector Reconciliation Program, this processes Lockboxes which end in error in Transmission Data, with error 96018 The exchange rate is not consistent with the receipt and/or transaction amount specified.
3. When adding the Exchange Rate and Rate Type to the Transmission Data and re-process, this does not work.
4. When added only Exchange Rate Type, it does process Lockboxes but the Receipt amount is wrong. For some reason the exchange rate used is 1, so that the PLN amount is unconverted to the EUR amount and the receipt is incorrect.