Unable to populate a file parameter mapped to a protocol in Capture

Hello, I'm currently running Compose 2023 SP2 (23.1.200.265107) and have a file parameter in a Capture task which is mapped to a protocol in Pipeline Pilot. This protocol generates a PDF file, then updates that parameter with the file. Prior to the 2023 SP2 upgrade, this process worked, however I am now receiving the error attached when I try to run the same process. The protocol itself runs successfully, so it appears the problem occurs when trying to populate the file parameter. I've also included the subprotocol which updates the parameter. ​​​​​​​Thanks in advance for any help.​​​​​​​