Hi Daniel. It's already supported. There are no restrictions at WIFE to create or parse those messages.
Also notice we added a helper method at SwiftMessage that checks if the message is a cover payment, based on the content of the User Header (block3). (CVS version)
That's because your message is being interpreted as a SYSTEM message and you are trying to create a FIN (USER TO USER) message.
**What is the content of your Block 1 and Block 2?**
Default writer logic will create a FIN message, unless:
- List item Application identifier at Block1 is NOT 'F' OR service identifier NOT '01'
- List item Message type at Block2 is category 0.
